Cessna 152 spin integrity

I was watching the 50-something spins done in a 152 on youtube and it
got me thinking;

I seem to remember being taught during commercial training that spins
do not greatly increase G forces on the airplane, is this true?

I also remember being warned "no spin is exactly the same or
predictable, so DON'T do them solo! Was this just a warning from my
school so we wouldn't screw up their gyros or are spins indeed
possibly very dangerous inherently for some reason?

I would like to try some solo next time I'm up just for fun but may
take a willing CFI along (or fellow pilot) just in case.

Would 50-something spins compromise a Cessna 150 or 152's structure?

Another thing I'd be concerned about was getting overly dizzy beyond a
handful of spins.

Ricky