Who else gets sleepy after a workout?

I went for another swim this morning, in my new swimsuit which i love! And now, 2 hours later, I'm getting. very. sleeeeeepy.

Do you guys get sleepy after a workout?

I lost a ton of weight a ton of years ago and at the time, tried many times to do morning workouts and then go to work, but I just couldn't get anything done because I'd be either feeling week, way too relaxed and always very sleepy. I was in pretty decent shape at the time, so I'm thinking it's not a weight issue.

Or on the weekends if i tried it, it would just kill the rest of my day.

So i took to a nighttime workout which worked well because i'd go on the way home from work and then sleep well.

These days, I'm at home, and schedule-wise, it's just better to work out in the morning first thing, then shower and go on with my day. Then i can spend my evenings with my husband. I'm also afraid if i leave the workout to the evening, it might not happen.

Has anyone else experienced this? Any thoughts?