Bladder infection. You likely have a bladder infection. .. Bacteria in the urinary tract. It is very common in pregnancy. You should see your primary provider as soon as possible to prevent the infection from spreading to your kidneys or blood stream.
Rule out infection. You need to get a urinalysis. May also be due to compression of urethra against pubic bone by an enlarging uterus. Or combination of this plus uti. Good luck.