Saying that it seemed to start when you started running suggests to me that it's likely that you can fix it with a regular daily yoga regimen. (my theory would be that you've been running either improperly, or improperly stretched, and have cramped a deep muscle, which is pulling from your shoulder and neck down through the opposite leg)

you may still want to check with a doctor if light stretching causes exceptional pain. the doc has one cool thing you don't have: xrays; and can tell if you have any more significant damage (torn ligaments, tendons, microfractures, etc)

I know that when I first started running, I wasn't doing it right, so you are probably right. Yoga is something that I want to get into, but every time I try it, I don't do it again. It's a little slow-paced for me, so I get bored. However, I know that it would help with issues like these.

You're right about the X-Ray. I unfortunately don't have one, so I need to get to the doctor. =)

my shoulder was fine untill a couple days ago when i played a baseball game and then my shoulder popped. It didnt dislocate. but it just popped, as if i cracked a knuckle. and now it hurts to throw or raise my arm.

Shoulder Pain Treatment