Any medical Moms out there?? Pretty sure I re-tore the MCL in my right knee.

Bekkah • Washington State🎣🌲Country Grown
I got up from my desk and there was a really loud crack and now it feels stuck in the socket and I'm limping. It's getting harder to walk on and my knee is very swollen and there's a little sac of fluid near my kneecap that is hot to the touch. I initially injured my right knee in January 2015 and tore the MCL. Any input would be greatly appreciated.