Vim Stuck In Insert Mode

Problem

I've been using Vim for several months now via my web host (they allow putty access). All of a sudden, the key has become unresponsive. I cannot exist insert or any other mode by simply hitting escape. I have to hit which brings up the help in vim and kicks me into command mode. I'm most certain that my escape key on my keyboard is functioning fine since all of my windows shortcuts that use the escape key operate normally. I know this is a ridiculous question and I'm certain there's a lot more to look into regarding a solution. What I really need is a solid lead as to where to start looking. Things that might help: I'm using vim via putty I'm logging in using jailshell I'm not root