Might be worth looking at the supplements you are using and at the very least googling them and finding out if others have had similar issues. Me and the guys at my gym throw all sorts of stuff down our throats, and all of us have had to stop even a legal supplement because it has caused stomach problems or headaches. It is annoying to have to do that, as it can be throwing money down the toilet {literally sometimes!!} , but if your problem stops you at least know what it is then. And you don't need to see a doctor.
Creatine js generally okay, providing you are sensible with the amount and as the guy above said drink water, but not all creatine is created equal and some especially cheap quality stuff can cause bloating and other problems no matter how much water you drink.Someone at my gym bought a load of chinese made creatine, it was so cheap it went by the bucket load down there guy made a real profit , many got sick from it.
.Other ingredients in pre workouts and protein shakes could cause a problem if you are allergic to them. I remember having a problem with a creatine called krealkyn that is specifically meant not to cause bloating!, I told someone in the gym I was stopping it, so he took it off my hands, and he was sitting on the toilet all night after using it!! He then threw it in the trash. I have took a multivitamin, an expensive one made by a company called reflex,that gave me a horrific one sided headache like I have never had before, while training, I didnt take it again and never got that headache again. It was weird because it was in my eye and affected my sight for a while.
I know a dude who took a prohormone, that gave him such bad pain in his balls he had to go to hospital. Where they treated him like shyt, apparently drinking loads of alchohol is fine though...
anyhow point is, many of these supplements arent sugar water, they have affects positive and negative even the legal ones. They have to or people wouldn't buy them again if they were all benign. Work well for some,not for others. And don't place too much trust in online reviews.I like to talk to guys I train with in the gym ,see what they are using .
Personally I'd would stop it and try a different one.