I also have pain in my lower left side when I am exercising. I couldn't figure it out what it is. I know that running and a lot of movement can release gasses in your system but it didn't feel like that. So here's what I did. I drink a lot of water normally. Instead of taking any sips right before I worked out I will make sure I drink at least four cups of water before I work out and make sure I stop drinking at least one hour before working out. It helped so much. That was the only time I didn't get the pain! Hope this helps!
But to be sure just go see your doc.
I wanted to tell you that I have also had the same problems occur during exercise. I did not realize it but I had a huge benine cyst on my lower right ovary. It was 15 pounds. I am much better now. But I have started back exercising now it has been two years since. And in January they told me I had another cyst on the other ovary. It has been about 9 months since I saw the gynecologist. And I just now started feeling the same again. I am hurting in my side and it is sharp pain. I was uncomfortable before alot. I could not get comfortable at all. I am better this one is small. So if you havent already. You might want to get them to check you for a cyst.
HI I WAS READING YOUR POST AND I REMEMBERED THAT I HAD HEARD SOMETHING LIKE THAT ON ONE OF THE OTHER FORUMS IN THIS SITE. JUST GO BACK AND GO TO WOMEN'S HEALTH IT'S POSTED "MY DAUGHTER HAS A PROBLEM" MAYBE IT'S SOMETHING YOU MIGHT WANT TO READ, MAYBE NOT. JUST THOUGHT I WOULD TELL YOU. TAKE CARE