Anyone else having this problem?

Yeah, I get it quite a bit recently. There's a fix on the forums I believe. I can't remember it right now though, sorry!

Just kill the process and re-open the launcher.

Just close, re-open, close re-open, close re-open. Eventually it will give you a message Another instance is open, close the previous one? Or something like that, click yes and there you go. If not restart, that's a sure fix for me.

close the program, cancel the load bar thing, click the logo if its still there, terminate launcher, try loading again.