Weird problem with G-mod

Whenever I play, this happens.

It seems to be a problem with the sky thingy or something? Whenever I look up into the sky, it like freezes everything i see, and then i move and it freezes that. Any quick fixes, and does anyone know the cause?

Indoors, without the sky, everything is fine.

Also, many of my add-on weapons seem to have their visible skins removed. Also, a bunch of them have no sound. And my character has new hands.

Looks like you have a missing game. CS:S, TF2, Ep2 ect.

problem fixed thank you.

Can you tell us how you fixed it?

A bunch of my games had been checked off in the extensions list thing. Checked em and restarted Gmod, all was good.