Being a 25 year old male. And being a decent size, I just do not know if the following is normal for a bloke like me to happen to:

Whenever I have sexual intercourse, masturbation of oral, and I ejaculate, my cock goes flaccid straight after. And I was wondering if this is a normal thing to happen to a bloke, or if I am meant to stay up for a while after?

Donot worry! It is normal

Totally normal dude.

That blood HAS to get back to your brain before you black out!

All my lovers went flaccid after ejaculating... it's normal and healthy. :D

If it doesn't then you have cause to worry. But no, its totally normal.

Every male is different. The male repro system is simply designed that way... once you have finished, blood will leave those capillaries to become reoxygenated. As far as your central nervous system is concerned, once you've , your job is finished, biologically speaking. At that point you enter a period known as refractory time; i.e. the time it takes before you can become erect again. Depending on age and general health of the individual, this can happen in as little as several minutes upwards of 24-48 hours. At your age and depending what the turn on is, it shouldn't take long to get it up again, though the erection may not be as hard the second time round. I know this is more info that you asked for mate, just thought an explanation would help. Cheers.

Just piling on the above advice.

Orgasm and ejaculation are actually two separate events that are intimately tied... its commonly accepted that the event of emission and ejaculation causes a refractory period, during which a strong erection is not possible.

If your partner is interested in more sex and your refractory period is too long, id suggest oral on her to orgasm first, then intercourse so you get "yours" and she gets another chance.