Can Faitgue, Frequent Urination And Tender Breasts Mean Pregnancy?

i had unprotected sex probably 2 months ago now,(i wasnt on any contraception) we used the withrawal method & he wasn't close to ejaculating when he withdrew. i went to my gp a few days after because i was peeing alot, he couldnt find anything wrong and did a test for chlamydia which came up negative....but lately my boobs have been tender and i am still peeing alot. i went out to drink the other day and i got horrible cramps, when i drink something it flushes straight through my body but it doesnt feel like the liquid is all gone. could i be pregnant ?!?! i thought maybe it could be diabetes since i am also getting tired alot, and its in the family. oh and im now on the pill...what do you think?!