Why am I peeing so much?

I pee all the time! This has been going on for about 2-3 weeks. I went to the doctor's and they did a urine culture, CBC, pregnancy test...the works. They say nothing is wrong with me. No UTI, I am not pregnant and my sugar is excellent. I am currently being treated for Grave's disease, which is under control. I saw my specialist for that today who comfimed that peeing had nothing to do with my thyroid. I wake up about 2-4 times a night to pee. It doesn't burn or hurt and I have no cramping (except from holding it in) or pain. I am beginning to think I am just nervous or something and I am thinking about it and making myself pee, but I think that sounds stupid. HELP! Does anyone have any ideas as to what is going on?
BTW I am 23 yrs. old, I had a kid 2 years ago and I have has 2 UTIs in the last 3 months. Before that never had one in my life.Why am I peeing so much?
Detruser instability can give you the urge to pee constantly with only a small amount in your bladder.
Your detruser controls the urge to urinate when it is time. When it becomes unstable theurge comes all the time.
It a matter of retraining yourself.
A Continance Nurse is very helpful with frequent urination.
Has your doctor considered interstitial cystitis? It can cause frequent urination. I have had it, and it happened after I had a few UTI's. I think what happens is that the bladder lining gets irritated from the infections, and then the body starts to attack the layer that is underneath the bladder lining. Not all doctors are familiar with it, and not all urologists, either. But it does exist, it is treatable, and you can find out more about it in the sources below. Good luck, and I hope you can get some relief.