I think kids get a little clingy after being sick, it is very common, they are still not 100%, they had mommy's undivided attention and I think when they start feeling better they still crave that attention. I know it took a few days after being sick for my kids to readjust, hee hee.
I would do everything you can to keep his bedtime the same time every night. There are of course exceptions but if you have a very set schedule 90% of the time it will help a ton. Kids at the age of two especially need a consistent bedtime and routine. It helps their bodies set up for bedtime and their mind.
Then you said you bring him into bed, of course he is going to wake up and now expects that now.
It has become a habit. Do not let him come into your bed, if he is really upset, rub his back, settle him back in but do not allow him to get up. Do not run in with a cup, have him take a sip of water before bed and that is it, no more drinks at night, remove cups, drinks from his room. If you are doing potty training anytime soon, having drinks in the room is not a good idea at all either. For night time potty training they do not need anything at all during the night.
Growing pains can happen, give him some tylenol/motrin for that and you need to figure out if he is saying things hurt or if they truly do. Like have him point to where it hurts, have him tell you if it is bad pain or little pain. If it is in the same place for a few nights then I would take him in just to be safe. Growing pains can hurt and cause muscles type ache feeling.
Also a bright room will not let his internal clock tell him it is time to sleep. I NEVER used any night lights as that can really mess up their sleep habits/patterns until they are older. If you use one make sure it is dim. I just gave my son one last year when he was potty trained so he can see when he gets up to pee at night. So the nightlight may be adding to the problem too. Go get glow in the dark stars/planets and before bed put the light on in his room, they are cool and kids love to look at them as they glow after you turn the lights off.
Another thought if you think it is bad dreams is get a dream catcher, my mother in law gave my son one and we hung it over his bed, suppose to take all the bad dreams away, it worked, not sure how, but maybe it convinced my son it worked and it did. Also make sure to read happy upbeat stories before bed time.