Breastfeeding and bra sizes...?

Alright. I have been feeding exclusively for a little over two months now so my supply is well established. I was a size 36 D before pregnancy and at about the 5th month I went up a bra size. I thought maybe it was from the weight gain and such b/c I discovered a love for twinkies I didn't have before pregnancy and gained 50 pds lol. I thought though that after I lost all the weight I would go back down to my normal bra size. Well...I have since lost everything but those last 5 VERY stubborn pounds and I am still wearing a DD. Am I this size b/c I am still feeding...or is this only temporary. I would like to go buy some nice bras and get out of these stretchy nursing bras but I am not willing to spend 50 bucks on one bra if I'm only going to be able to wear it for a month or two. The other thing...I'm 5 1 and wear a size 28 jean. I look RIDICULOUS this big (think pam anderson people). It looks really unnatural. Will I ever go back to the size I was?