I'm male. After I mastrubate, I'm very sleepy and then for the whole day, my eyes are tired (my eye lids heavy). This is not normal, is it?Ma

There is a hormone, I don't remember the exact name for it, that is released after a man ejaculates that can make you tired. It seems pretty normal, but if you are literally falling asleep sitting up then you may want to talk to a doctor.

This is different to ejaculation during sex. There I'm relaxed, perhaps sedate; mastrubation is not the same. I feel doppy for hours after.

Then I would go see a doctor or Google it and see what comes up

It seems that ejaculating during intercourse gives you maximum pleasure in your mind as well as your body. :)

Ejaculating from masturbation has some negative mental connotations for you hence, the inability to bounce back from a session.

Many hormones are released, oxytocin adrenaline as well as serotonin endorphins, endomorphins etc. your response is typical after orgasm (male or female).

I would suggest that the cause of heavy eyelids is because you are doing it to excess when you should be sleeping.

Well perhaps you should only do it at night

I can only say that it helps me go to sleep. Great way to cure insomnia.