dont know if this is even possible but have been struggling these last few days and dont know if its just post surgery stuff or if i have a problem

my burning in my legs came back with a bang but its more a hot itchy legs then the burning pain of before. now today i took an anti histimanine tablet and everything settled down and went back to blissful pain relief can you be allergic to your device ? or is this just a coincidence?? little confused and dont want to call rep and sound like a hypo chondriac either so though i would pass it by my very smart scs buddies?