Recently, I [23M] have started getting intimate with my girlfriend [21F]. The thing though is that when she gives me a handjob, my arms start to go numb, kind of like when the circulation gets cut off, but more intense. The numbness gets more intense the closer I am to orgasm. Is this something I should be worried about or is it normal? I should note that I am in shape and have had no history of cardiac issues, and that this numbness does not occur during other acts like penetration or oral.