Had a diagnosis of tennis elbow in my right arm while working on my computer. A week later my left arm became affected. 6 weeks with OT and physio and now im told they don't know what I have. My fingers now tingling and wrist/forearm pain too. Help!

Nerve or muscle. . By your description of symptoms, you may have something related to the muscles of the forearm or the nerves going down to the forearm. If it's a nerve issue, it could originate at the elbows or from the fingertips, traveling backwards. Regardless, it seems that you need some blood testing and perhaps an MRI of the elbows.