I am in a similar position. I had five classes this semester, and I wasn't doing them well. I'm super concerned about my GPA, because I need to apply to grad school.

I ended up dropping a mandatory History class. I will have to take it eventually, but it was causing me the most grief, and on the up side, I've done half the work for when I eventually do take it again.

You can only manage what you can manage. I don't think there's much point in just barely hanging on. You may be able to keep your courses and qualify for accommodations which may help you out. Have you looked into that possibility?