Hip Pain? Not From Running but Swimming?

I have suffered with an annoying pain in my hip that has been managed for years with Active Release Therapy, Graston and Stretching.  I always figured it was from running. Lets face it many common injuries are from running but if your a runner you keep running and find ways to manage things.  I know my running form isn't perfect and I have always tried to work on some of my imperfections.  Recently I was forced to take time off from swimming.  I was out of the pool for 2.5 months.  I have not done that since I started triathlons over 10 years ago.  I was able to run and bike so I did that a lot.  I even got up to running 35-40 miles a week.  I love to run so I took full advantage of my time out of the pool.  I didn't realize for the entire time I was out of the pool my hip didn't hurt at all.  In fact it only occurred to me that it wasn't hurting when I recently got back in the pool.  The first few days back in the pool it was an easy swim and I didn't have any problems.  The next few workouts were a little longer.  After two days in a row of longer swims I was  feeling the dull ache in my hip halfway into the swim.  A bright light went off in my brain.  This pain has been caused from swimming all along!  We often think of swimming injuries connected with shoulders but my left hip?  What could I possibly be doing wrong in the pool to cause this pain.  As a coach I am certainly going to get to the bottom of it!  I have been told by two different coaches that I don't rotate enough and I only breath to my left (the side of my hips that hurts). Could this be part of my problem?  I don't know but I will try to find out. I have an appointment with my Chiropractor tomorrow and hopefully we can get to the bottom of this!  I will have someone video me in the pool to check out my kick and rotation.