Arm problem

[will189]

I'm new to this forum & this is my first post. I am 37 years old and have been weight training off and on for the past 6 years. I have really been dedicated the past 12 months (probably have over trained). I'm not a real strong guy, but today I had a pretty big setback I think. I was working my shoulders & triceps today and noticed I was down a little bit on my shoulder presses and had a little discomfort in my left arm, but I have had off days before, and it wasn't till I moved to my triceps that I found the problem. I usually start off with lying Dbell presses of 8 reps 40lbs, but I couldn't even get 1 with my left arm. I have some discomfort (really can't call it pain) just above my arm joint. I'm thinking of taking a week off of everything and see what happens. Anyone else ever have a problem similar to this, or have any idea what it might be?
Sorry if this is a dumb question, but I'm a little bummed out about the prospect of this being a long layoff.

Thanks!

[UConnJulie]

Please read the sticky at the top of the subforum, and reply to the questions. A photo with an arrow pointing to your pain can also be helpful.