I have a question about l infections yeast and BV?

Heres the history. I went to to urgent care at 15 weeks due to a horrible l irritation. I ume it was a yeast infection due to the white discharge, fishy smell, burning and itching. So the on call practionioner did not want to do a l exam because she said I was too early in pregnancy. She had me swipe the inside of my and she looked at the discharge under a microscope. She said that she did not find yeast, trich, or BV. He said it was just an irritation and told me to use vagisil and dove scentless soap. My irritation continued to torture me. Two weeks later I had my doctors appointment and my doc did a l exam and she put the swab under a microscope and she said that I did have a mid case of BV and she prescribe me metronidozole(something like that), which is an antibotic. It was a 7 day treatment and I got relief on the 3rd day but the symptoms came back and worst. So now I am depress because I am so miserable. So yesterday at my 21 weeks check up I told my doc I am still itching burning and all, so they check my urine and found 2+ leukyocytes(something like that) so she said it was a UTI but when she did my l exam she said just by the look of it, she new it was a raging yeast infection but she was too lazy to put it under the microscope. I ask about the uti they found and she said it was just due to the discharge from the yeast infection. She prescribe we 2 med. Diflucan and some yeast infection creme. The diflucan is a 2day treatment and I began the creme after I finish the diflucan if my symptoms persist. Ok so heres the question Did the antibiotics cause the yeast infection? I took my first diflucan pill yesterday and a couple hours later I notice a bunch of vaginal mucus dicharge yellowish with chunks in it, coming out of my vagina. I been having this discharge all of along but it never alot like this. Does this mean the pill is working and thats just chunks of bacteria coming from my vagina or do i still have bv. I know some people say the bacteria just dissolves and you cant see it come out. I am not experiencing any itching or burning and the foul smell is just yeasty now as of yesterday.