Terminal hang after entering login SSH password on server. Did I just got hacked?

I was doing routine maintenance on my server. As usual, after connecting successfully to my server on port 22, I was shown a login prompt:

$ ssh admin@1.2.3.4
admin@1.2.3.4's password:

Seeing no warning whatsover, I entered my password. Then my terminal hanged and the black rectangular cursor key stopped flashing. The desktop is still functioning as normal. I tried Crtl + C to cancel previous action. It didn't respond. I quickly close the terminal.

Did I just got hacked? How do I know if this is a software glitch or security issue? Not knowing whether I have successfully logged in, what would you do in my situation?