Bummer Run!

This morning I got up and was totally excited to do my run today. It was my first run with my new Garmin Forerunner watch! My goal today was to do 5 miles. So I started my run and was feeling great and around mile 2 I was feeling so great that I was contemplating doing more as I was enjoying playing with my new watch. About mile 2.73 I got the worst die ache of my life!! I felt like something was exploding inside my body on the right side. It was so bad that I headed home so I only ended up doing 3.63 miles. This is not the first time that a side ache as disrupted my run. I asked my sis in law Ang what the possible causes of this could be and she said that I wasn't drinking enough water. So I thought I was drinking a lot but I guess I am going to have increase my intake even more because I do not want this to happen again and ruin a perfectly good run!!!