So I'm still having a rough time concentrating since having surgery. I can focus on one thing for a short period of time no worries but trying to do these complex assignments that I have from uni is proving to be very difficult.

Did anyone else experience a prolonged sluggish brain after having anesthetic? 

That is a very common affect of a general anesthetic. It can take a few months to get over all the physiological effects of GA.

This really sucks. I have aptitude testing in 2 weeks as part of university admissions testing. I have missed the deadline to apply for special consideration because i had no idea that anesthetic would do this   

Don't fret it, plenty of sleep and healthy life style will really help.

I had a long period of lethargy from anaesthetic.I was very sluggish and slept 18 hours a day.