Suggest Remedy For Dizziness Post Morning Workout

During the morning I work out at the gym five days a weeks for 2 hours approx. At the end of each
workout i lay on a mat and stretch out my muscles. This is the only time I lay down after my workout and during the laying down i feel light headed. If i were to jump up quickly i would get so heavy on the dizziness and must remain stable til it goes away,,,,can you help,,, this have began November 8, 14