I had my surgery in the middle of the semester with 15 hours of senior level honor science courses and for me the first week back was the toughest. After that I got a surge of energy and wanted to study. I could study longer and it seemed I understood the material better. I finished with all A's and one B so you can do it. Just listen to your body and stay hydrated also you might want to let your profs know that your having surgery and if there are complications you might miss school all my profs understood and made online videos for me even though I didnt have any problems