The people who are telling you to chill? Lies. Lies, I tell you.
I desperately wish that I had pre-studied anatomy. And I had taken A&P courses before as part of my nursing degree. And then worked in an OR where I got to see a lot of that cool anatomy in vivo. I'm still struggling to keep up now, and wish I had just a little more time to review.
No, you aren't going to learn everything to the level of detail you will need when you get to medical school... but I think of it like painting a masterpiece. At first, you just make rough sketches, figure out where the shapes go. Then, you go over the entire work again and firm up your plans about what will go where. You move from pencil to ink. Then, you come in with the big areas of color. Each pass brings a little more detail. You can keep studying anatomy your entire life and never get every detail down pat, but the more times you see it, the deeper and more complete your understanding of it will be.
And anatomy is absolutely the foundation of so much else that you will need to learn. There is no such thing as overstudying it.
Atlases are great. Flashcards are great. But the majority of our class is currently heavily addicted to youtube. We trade great youtube videos, of dissections, of diagrams and explanations. I will share a few of my gems:
These dissection videos have saved my LIFE:
Noted Anatomist - not many people seem to have seen his vids, but they are GOLD:
https://www.youtube.com/channel/UCe9lb3da4XAnN7v3ciTyquQ/playlists
Dr. Preddy - fast, fun, great mneumonics for the extremities:
https://www.youtube.com/playlist?list=PLhqd4CB6o3UXzBNuNPPeqwUs48MgftwDp
Anything at all by Access Anatomy:
I could go on and on.
Look, I'm not saying that you have to spend 12 hours a day on this, but what would be the harm in watching an hour or two of anatomy videos when you are goofing off on the internet anyway? It doesn't have to seriously cut into your chillaxing, and you can still come in ahead of where you would have been without it.