error 500 after installing and running

I keep getting 500 ISE errors, and after trying and retrying to finish the smushing and not being able to avoid the ISEs, I tried to access my plugins folder and got a 500 ISE on that! I left it for a day and just tried again, but I cannot access my plugins at all.

Everything was working fine before I tried to smush so many images. That's when the 500 ISEs started to show up. I will contac the hosting service to see what they can do but thought I should talk to you first since it was when using Smush that it started to happen