Yep, complete tear. I just had mine done, Tommy John on 2/29. Not to scare you but what you're describing sounds like my symptoms. Numbness/tingling in your pinky and ring fingers are also a dead give away.
Mostly it just felt really unstable, especially when valgus stress was put on it. This type of injury really needs an MRI, I think -I actually passed the Valgus stress test from my doc. Also, I had some tightness and weakness whenever I tried supinated (palms up?) curls. The nature of the activity that led to the injury can help as well. UCL injuries are common in baseball but are chronic. Mine was acute (submission in Jiu Jitsu). I hope you feel better. Really, you should see an Ortho or a PT.
Thanks for the comments. Luckily I have no tingling in my pinky or other fingers, and no pain when doing any lifts, just that feeling of tightness, which leads me to think it might be a sprain and not a tear.
I've focused on really keeping my elbows in, no matter what exercise I'm doing, and have switched to neutral grip for almost everything (military press, chest press, etc.).
Do you think supinated curls are bad for elbows in general? Anybody else have experience with a sprained or torn UCL?