If you're only 3 days post vas, I'd be careful how much you blow your load. If I could go back, I would've laid in bed for two weeks and not moved. Probably even taken laxatives to avoid any kind of straining. You're in a very small window post surgery that if you screw it up, it could affect you the rest of your life. Don't risk it. Docs don't emphasize this enough.
I think a lot of the orgasm disbelief within medicine is a lack of understand of the process. After 24 specialists in 11 months, 50 blood tests, 4 mri's, I've painfully come to the conclusion that medicine knows 1/3 as much as I realized. Don't get me wrong, there are some smart people out there but I have obvious problems and can't get straight answers about anything. I think often times they say "this doesn't cause that" when in fact it should say "we simply don't know for sure" and "everyone is different".
I didn't have any major sex issues until the 6 month mark. Now it's soft ED, lack of sensation and minimal libido. I wouldn't rule out hormones either. There are more papers documenting hormone changes after vas than papers that say there's no change. Unfortunately money incentives within medicine latch on to the papers that support their agendas. Case in point, there are research papers within 10 years of publication that focus on lutenizing hormone. One paper shows LH nearly doubles post vas (not good), the next shows a 15% increase, the latest shows no change. Who's right? Who's lying? What paper does every urologist have memorized and quote when the question comes up? There's something big going on within medicine pertaining to vasectomies.