ok, so, a problem I've had is that Im parrying right when the first guy is swinging his sword, and I'm rapidly clicking right mouse while I get killed, but Im right clicking while he's swinging his sword, am I not doing it correctly or?
You don't have to rapidly click, simply holding the block is enough to parry the incoming attack. After a successful parry you get back to idle state, so before another attack you have to press block again.