By the way, if you decide to test the allergy hypothesis, try to find baby soap or laundry soap bars ("sapun za prane" in Bulgarian, it may look like it is homemade - brownish - or even better get some from someone that has real homemade bars, it doesn't smell nice but does the job and has nothing added to it). And indeed, as that doctor suggested, you may want to wash your underwear by hand with "sapun za prane" if it comes to contact with your body.