For the past week, I have not been able to fully extend my arm because of pain. It feels like a whole muscle or vein that goes up my entire arm is really sore. Iy only hurts when I try to extend my arm or push on it. I haven't hurt my arm. Any ideas what this is?

Hello,
I Have This But On My Leg. It Works All The Same Way. The Most Likest Cause Is Either A Sprain Or A Strain, Or It Could Be As Simple As A Pulled Muscle. If Your Arm Gets Swollen Put Ice On, But Only For 10 Minutes A Time Otherwise You'll Burn Your Arm.

Hope This Helps

Auntie Zak