So I get in my car yesterday, roll my window down, and it wont go back up. I cant leave it down since it might rain or invite thieves (I live in apts) so I reach in through the window crack and pull my window all the way up and tape it up so it wont fall back down.

Now without the tape holding it up there is no resistance stopping it from going down. Pushing up on the window switch doesn't seem to have any effect. However, pushing down on the window switch seems to want to pull the window down even against the tape holding it up from falling.

I'm thinking regulator, not motor or switch. Any input or experience with this would be greatly appreciated.

 

You are thinking right.
There are some discussion + DIY threads in here (you can do a search on "window regulator replacement"), or you can glance over at AudiWorld.
good luck.

 

Check the switch first. See if you can complete the circuit in both positions.