It really depends on the antibiotics and diflucan, you cannot generalize and say all antibiotics make the problem worse, but it's generally assumed that yes antibiotics kill good bacteria and you need good bacteria to fight off candida. Your doctor prescribed antibiotics as well as diflucan for a yeast infection.
Although it certainly doesn't look good that the infestation hasn't cleared up at all. My suggestion would be to start taking probiotics the next time he gives you antibiotics as well as there's no reason you shouldn't. You can also consider a good candida diet.