I don't mean to scaremonger but do take it seriously. I'll second ice and ibuprofen gel massage for pain relief. Also as ACP says, the best remedy is rest. I have a weakness there and have suffered with both elbows on and off for ten years. Despite physiotherapy and acupuncture it grew so bad at its peak that I had cortisone injections and ultimately surgery but it was prolonged rest that finally eased the condition.
People may scoff but this condition can become chronic and very debillitating. For almost a year I couldn't do the simplest things like tie shoelaces and do up buttons. Prolonged rest is easier said than done but in bad cases might be essential.
Be aware that the finger tendons attach to the elbow so repeatedly flicking a mouse button can exacerbate the condition and do unexpected damage there. I believe extensive use of a PC for work triggered my condition.
Good luck.