I might talk to the Doc about seeing an allergist. . Might not be related to the gall bladder removal at all. Then again that could be the problem. I went through hives last summer during the pandemic and it was hell (itching,etc. ) Kept waking up in the middle of the night taking stuff like Zyrtec and Allegra. Went to an allergist who was quite frank and said "unless we can pinpoint exactly what it is you are allergic too we may never know the origin". He was right we never found out but after a couple of months it simply disappeared.