My resting heart rate is 40bpm. I normally do long slow runs and interval cross training. Yesterday moring weather was bad, cold, snow/rain mix and I ran in a 5 mile cross country race. Before it, I didn't feel like running, sleepy so I drank a few cups of coffee. I also drank a lot of water as well. During the race I felt different than any others that I've ran, my muscles tightenend up and I thought I may have to drop out which would have been a first for me. I walked some of it going up a steep hill that in the past I could run. On the way back it's mostly down hill so I took advantage to try to make up some time so I flew. When I crossed the finish line I thought I was going to have a heart attack. I know my heart has never beat that fast before and everything was blurry and I was dizzy. I layed down right away since I couldn't hardly see where I was at anyway. My husband got me up to make me walk right away since he was afraid that if I stayed in the position too long my muscles would go into cramps. I felt dizzy for about 20 minutes after the race. I'm very concerned of why my heart was racing so fast, was it the caffine from the coffee? Maybe the weather? It really did scare me. I have won numerous overall fastest female runner at races and never felt like that before.