Turtwig, I had the opportunity do to something like that, except it was night classes at 2 in the morning. It would have meant getting two semesters of university done by the time I graduate... But I honestly think it wasn't worth it on top of my exams.
I did it for a few weeks (this meant I had to quit my only job since) and was going extremely well (Had a single panic attack in the middle of an assembly... Great timing
) academically, but I had to let it go just due to the fact I was getting only 1 and a half hours sleep each night.
You're extremely lucky to shave off half your time at college, although I know how horrible panic attacks can be.
(I had severe anxiety between the age of 6-12).
How long have you been taking the classes?