Reddit mentions of Milk Saver Breast Shells Nursing Cups - Protect Sore Nipples for Breastfeeding - Breastmilk Collector Catcher for Nursing Moms - Soft and Flexible Silicone Material Easy to Clean - Reusable - 2 Pack

Cute picture, but so sorry about the mastitis! My sister had it with one of her kids, and it sounds sooo painful!

A few thoughts, speaking as someone who has oversupply problems and overcame it....

1. Your LC sounds pretty good, I'd do another session with her now that this has come up and see what she says.
   
2. For the uneven boobs, I have the same problem. I always feed first with the "bad" (in your case, left) boob then switch to the one with more supply.
   
3. If you're getting a significant amount of letdown while you're feeding with your left, you can try wearing a letdown shell (there are several kinds, available through Medella, Milkies, etc.) on your right when you're feeding. I have been able to store/freeze between 2-4 oz daily this way, by accumulating it throughout the day instead of just letting it leak onto a nursing pad. Your LC may be able to give you a freebie in this category too.
   
4. You're going to hate this one at first, but I'd avoid pumping as much as possible, especially if you're using an electric pump. That's probably what is giving you oversupply is that the electric pump is ramping up your boobs on top of breastfeeding. The breasts will adjust if you're exclusively breastfeeding, especially if your milk is still coming in (it takes 3-4 months to reach your full milk supply). If you're uncomfortable, I'd recommend hand expressing. When I had an oversupply I'd take showers and hand express it out until it no longer hurt, this worked really well for me. Try expressing before the baby feeds, so that you can get a deeper latch. Once they've ramped down, try to avoid hand expressing as much as you are comfortable.
   
5. A few people on this thread are recommending the haaka pump. I LOVE this pump. But, I didn't realize this fully at first, it serves a different function for people with oversupply. It stays on with suction so it is a lot stronger than a letdown shell....and as a person with oversupply, it was giving me oversupply issues since it was acting like a pump. But if you just use it at an overnight feeding or are at a point when you feel full when you're not feeding, it's useful in that way so that you never have to use an electric pump unless you're at work. Your LC may have opinions about this as well....the haaka gets mixed reviews on reddit sometimes, I think.
   
6. If you feel feel a clogged duct coming on, feed the baby on just that side for awhile, and try dangle feeding and a warm compress. For the warm compress, take a cup of dried rice and some water and microwave it, then put it in a plastic bag. Hand express where it feels "hard" on the boob for awhile, it should work its way out if you're diligent.
   
7. For hand expressing, I like to take a flange from an electric pump and just put it in the bottle, with the wide part facing out. That way I get a little "funnel" so I don't spill milk all over. ;)
   
   Good luck!!!

Things I forgot:

• waterproof crib sheets (put em all on so you can just take one off in the middle of the night
  
  
• wet bags if you’re trying cloth diapers
  
  
• more pacifiers
  
  
• white noise machine (someone gave me an old one but it broke fast)
  
  
• Velcro swaddles (it’s easier)
  
  
• fabric carrier, like the big scarf kind (way easier than the straps kind)
  
  
• baby monitor
  
  
• for breastfeeding: I liked silicon caps (think like pasties) but not at first! (I got mastitis while I was learning the schedule because the silicon caps don’t let anything out). I also tried these https://www.amazon.com/dp/B07H75C9Y3/ref=cm_sw_r_cp_api_i_COqSDbHEVP2QQ which were obvious on my large breasts but I wore them around the house and they were super convenient.
  
  
• Milk storage cups
  
  
• hand pump (easier and less time consuming than electric pump)
  
  
• pumping bra for electric pumping (you do not want to hold the flanges to your chest for a half hour or more, it’s depressing and you can’t scratch your nose)
  
  
• stroller that works for babies under a year: I got a stroller that a baby would sit in, totally didn’t realize it wouldn’t work until he’s good holding up his head. Ended up getting a good deal on a jogging stroller/car seat combo that worked out way better.
  
  
• postpartum underwear (I didn’t forget these but they were soooo handy and comfortable)
  
  Oh and we were totally blindsided by the fact that some hospitals try to jerk you around on the car seat, we were told (right before we were supposed to leave) that we had to take baby out in a car seat, and the one we had wasn’t a carrier type so my in laws ran out and bought one. I liked it better anyway, so luckily when I got the jogging stroller deal it came with a carrier type car seat that clicks into the stroller too.

Normal (unfortunately). If it turns to pain, then you probably have an issue to address. Lots of open air time helped me. I also used the below bc I leaked a lot or if we had people over visiting/helping and I didn't want my nips just totally out haha.
https://www.amazon.com/dp/B07H75C9Y3/ref=cm_sw_r_cp_apa_i_a0cvDb54Y6BDD