You don't have to tell your NS and they SHOULD NOT keep you out because you have epilepsy. Once you are in though, I would make sure someone knows in the event that you have a seizure. Everyone on my unit knows, most knew before I was hired because I did my preceptorship there, and it really helped out a couple years ago when I had a MAJOR seizure walking down the hall on the unit.
BTW-In Alabama, The Dept of Rehab Services assists with school, job placement, and monitors graduates for 1 year after graduation to ensure that they are not have any problems / discrimination, etc. You may want to check for something like this where you live.