left swollen upper arm

Why is my arm swollen by the back of my upper  left elbow?  Feels tender when i push on it. It is not black and blue.  

[Niffer991]

It's hard to say but if it is swollen then apply ice for 15 min then repeat to help reduce the swelling. See a doctor if it is still quite painful or problematic.
Maybe you walked against a wall or something and bruised it?

Jen

[Dr_Smita_S]

Hi

A swelling in the arm may be due to trauma, fracture, tumours or other causes. If you have any localized tenderness and pain, you should be consulting an orthopedic doctor at the earliest. An X-ray can reveal the exact cause.

Till that time, you should try to avoid using your left hand, take adequate rest, apply ice packs, and some OTC anti-inflammatory analgesic medication.

Hope it helps.