Manjaro immediately logs me back out when logging in

As the title says: every time I try to log in, the screen goes black for a couple seconds and I’m met with the login screen again. This doesn’t occur when i try logging in from the terminal (or whatever it’s called) from ctrl+alt+F2.

This strange behaviour started happening when I was trying stuff from a forum conversation (on the arch linux forum, just look up ‘firefox taking 30 seconds to start’) on how to fix firefox taking a long time to start up. I installed xinit and/or startx (i cant really remember which one) via the add/remove software app, and I restarted my pc, and now I’m in this situation.

Any help/suggestions are appreciated!

How about reverting what you did?
And perhaps explaining why you did it?
Because your reason for why you did it may not be the proper means to that end.
(I didn’t look for that forum conversation you mentioned)