Formication (tingly prickly sensation sometimes described like ants crawling on or beneath the skin) is a recognised symptom of hypoestrogenism.
However this should not normally involve visible hives or swelling, this sounds histamine mediated, like a reaction to something.
Certainly loss of ovarian hormones, which are naturally anti-inflammatory and immune modulating, can lead to people reacting to things they previously had no problems with.
If it were me, I would want estrogen and at least in the short term, an antihistamine, and if it continues possibly some allergy testing or elimination trials.
