Start of with resting. And after a couple of weeks, if you can find somebody who can check for muscular imbalances, and help you make a program to work on those would probably be the ideal way to about it.
I dont want to make any specific recommendations because A, you should see a specialist and B, doing a diagnosis and recommendation on what to do about it without having seen you in person is just not smart.
In my experience, the most injuries DG'ers sustain are due to posture/muscle imbalances. While these may go unnoticed in normal life (ie. low-activity), things like discgolf may bring these to light, even though a backhand throw has very little injury potential compared to a lot of other sports. (Most deskjockeys, including myself, get the forward pulled shoulders coupled with excessive lumbar curve. In my case I try to stretch my hip flexors, and use excersizes that target the posterior part of my body. So pull/chin-ups, squats/lunges/deadlifts, supine bridges, face-pulls and ab-rollouts are all very good excersizes for this
For tissue treatment check out, Active release technique which often works very well. http://www.activerelease.com/