Many issues after upgrading to Mojave

Hi all,

I'm on a Macbook Pro Retina 13-inch late 2013. I upgraded from High Sierra to Mojave a few days ago and everything seemed okay. Now all of a sudden every time I close my laptop I open it up to find the color display all wrong:

Turning it off and back on again seems to restore the usual colors but that comes with a whole new set of problems. When I turn it on, it'll chime, but the screen will stay black. I have to do this two or three times for it to finally boot up, which then can take up to ten minutes. Is anyone else having this problem, and how can I fix it? Money's tight right now and I really don't want to have to take it in for repairs or worse, get a new laptop.