I am in great physics PhD program in my first year, and classes aren't going all that well. Last semester I barely made it with a 3.0 gpa, which is the minimum required. I tried to study and work on the homework gradually, utilizing my classmates to bounce ideas off of. This was a big step forward for me, considering that throughout my undergraduate career I relied on last minute cramming and last minute "homeworking." But I guess it wasn't worth all that much because I didn't do great like I wanted to. I feel rather lost, and even though I really like physics, perhaps a PhD is not right for me if I can't get my act together? Well, I have completely regressed it seems. Because of this, I may do worse this semester. I just have no motivation. And I should right? I got into a great school, everyone is supportive, and I just got accepted into the research group I wanted. However, this group is high profile, and it is theoretical work. How can I hope to do such work if I can't even get A's in foundation classes like classical mechanics?! I feel that I am making a grave error in aiming too high. It's stressing me out a lot. I thought I could do it, get myself to try. But I keep sinking lower and lower. I know that part of this is due to mental illness, but I can't keep blaming it on that, it seems like a cop-out. I guess I just want to hear what other people have gone though, if I am really making a mistake in being in graduate school, or if it will ever get better. I know that ultimately I need to make decisions for myself, but it's hard for me to think that just a year ago when I got the acceptance letter, I was so darn happy and so excited to get my PhD, and now I just want to give up completely. Someone please help, anything will do.