Freshman year is tough. It's really hard to acclimate and find your place in things. It's important that you go, and I think if you started to go that you'd find your grades go up, too.
I know it sucks to go, and a mental health day once about every three months is about my max. Limit yourself. Study just 5 minutes a night. Small steps, and before you know it, you'll be doing better in no time.