You might have difficulty in getting meaningful answers on this site because it's based in the UK (and, to the best of my knowledge, we don't have any regular US contributors here at the moment).
The terms 'GPA', 'SAT' and 'ACT' simply don't exist within the British education system (and I suspect that many people on this site will need to google 'sophomore', as that's not a term used here either). So much of what you've written in your post will be largely meaningless to people reading it here in the UK. (Sorry!).
As long as you're doing the best that you can though, forget about grades and start enjoying the social life at university. I used to teach Year 13 (= US Grade 12) students and one of the key things I kept reminding them when they were considering embarking upon their university studies is that university is meant to be FUN. Yes, there's got to be a bit of hard work too but, even if you achieve a First Class Honours degree, you'll have wasted several years of your life if you haven't ENJOYED them. Stop worrying so much about your grades (and, in particular, whether you're doing better or worse than other students) and try to RELAX. A night out with your mates is just as valuable as a night slaving over equations ;-)