Reddit mentions of Human Anatomy (7th Edition)

Anatomy is a real pain in the ass, to really understand everything you have to start from the ground up, or bone to epidermis. The body is really complicated as you might expect and since evolution isn't perfect how somethings work don't make any sense. In an ideal world I would really suggest getting an anatomy textbook, sadly they're pretty expensive. This is mine but it's pretty expensive.

Since that's likely not the road you'll take I suggest anatomylearning.com and then supplementing with wikipedia (I've found it to be accurate and contain lots of pertinent info). From there expand your knowledge with external sites if you get into it. I've learned the most by seeing and touching cadavers so try to find labeled pictures, I don't have a good source for that because as I said I get to see the real thing. In the mean time I suggest staying away from joints, they have a high concentration of vessels and tendons. Your muscles were designed to protect your body, vessels and nerves are usually under them so if you really want to continue with this I'd suggest staying away from the forearms and legs (in anatomy that's between the knee and ankle). There're lots of tiny muscles there because of all the fine movements you have to do and it'd be easy to cut through them. I'd say you've been very lucky to have not caused permanent damage after all that cutting. Best of luck.