4 stroke 25hp slippage issues/shaft play

[stainless210]

I have a 2000 4 stroke 25hp, recently while fishing at the lake I hit an underwater object. The motor revved as if the prop slipped. I stopped then took off and as the boat planed and placed a load on the motor, the motor revved (slipped) again. I assumed I spun a hub. I took the prop to a repair shop to have the hub repaired and the tech said it did not look like the hub spun. I replaced it anyway. While replacing the new prop, I noticed I had a little up and down and side to side play in the prop shaft. Probably 1/8 inch (or less) play. Is this normal? or could my engine rev (slippage) be a broken gear? Any ideas?

[boats.net]

Remove gearcase oil drain screw and look for water or metal in oil, if do then do have a problem in gearcase.