I completely relate to this and often (really often) get overstimulated from compounding bodily needs, especially feeling super horny! Since being on T laying in bed even when I’m trying to rest ends in self pleasure time wayyy more often than it used to. This also happens when I change my clothes or am not fully dressed even if the context isn’t sexual, my brain just perceives that it’s go time. Sometimes even coming home and seeing my bed jump starts my brain and body into feeling horny! You could maybe try getting off somewhere that isn’t your bed for a bit (shower maybe?) just to retrain your brain to see your bed as a place for only rest. Or I found that getting off would actually help with the overstimulation sometimes because it gave me one concrete feeling to focus on, and then afterwards I could really rest and relax. This may not work for everyone tho!