Can dogs break out in small hives aka bully bumps dur to stress? Just recently my frenchie had a stressful day at the groomer. We went back the following day because the nails weren't trimmed probably and my frenchie started freaking out on the second visit. And no nails trimmed again. A day or two laters i noticed a few small hives than recently he had them all through the back, cheeks. And back.havent had times for to go to the vet but will do first thing tomorrow. Not sure if they are an. Environmental reaction , the stress he went thru at the groomer, flea bite or a chemical i used to clean my couch.