It's actually very dangerous to leave a UTI untreated as it can lead to kidney infection and kidney stones and eventually lead to natural termination of pregnancy. So you need to call your doctor. They'll give you antiobiotics and you'll just need to drink a lot of water and cranberry juice.
I found this site and I hope it is helpful to you:
http://www.americanpregnancy.org/pregnancycomplications/utiduringpreg.html
you probably have a uti, a bladder infection, or something. only way to take care of it is go to the doctor, they will test your urine, and if they find it, they will just give you some antibiotics to take care of it. until then, drink a lot of water, and cranberry juice mix, since cranberry juice by itself is kind of, not really the best tasting. I know drinking a lot isn't really the first thing you want to do, since it makes you urinate even more, i've experienced this myself a lot of times. during pregnancy you're more succeptible to getting a urinary tract infection. get to your doctor to have it taken care of before it gets worse, it will likely worsen every day if left untreated and can get very painful. i speak from experience. goodluck!
have you ever had a uti. some women get them i would go to the clinic and have a urinalysis done and goodluck sweetie.