I've been getting e-stim and ultrasound treatment on my elbow for tendonitis but does not seem to be getting better. Any other treatment ideas?

See your doctor. I recommend that you visit your physician regarding the specifics of your case but as suggestion you can try trigger point injections that my patients find helpful. Wishing you the best.
Modify and treat. 1. Make sure that epicondylitis is the true source of the pain 2. Ice and nsaids 3, take a good hard look at your program, add stretching and non irritating strengthening to your regimen try to strengthen you r grip and forearm without loading the extended elbow with the wrist fully flexedor raised with resistance 4. See a doctor to clarify 5 talk to the therapist or trainer.