Ok....first off, when we do not get enough rest, and when we are also under stress and you sound like you have barrels of it, we get sick. Butterflies in the chest and headaches, and dizziness are all part of sleep deprivation. Anxiety or worry can cause a rapid heart rate, as can anxiety attacks or panic attacks. When we are worried our stomachs crank out a lot more stomach acid and we may feel sick to our stomachs when that happens. It might be psychological, but the effects are physical and real. Get a new doctor. Then try the following: Start getting some magnesium and potassium into your bloodstream. Good Vitamin B complex vitamin tablets will help along with exercise. Eat a diet rich in dark, green leafy veggies and get some fresh fruit into your diet, bananas for example are great. Exercise by walking. Just a good brisk walk for at least an hour each day, anytime you can fit it in. If you do not live in a safe neighborhood, you can do laps at a local YMCA, or go to a mall and do laps around the mall for an hour. You may be having panic or anxiety attacks, they are common, can happen to anyone at anytime, even when you are not feeling nervous about anything in particular. They can cause a butterfly effect in the chest and raise your heart rate. The change in diet will help greatly with this, and the vitamins will too. Exercise takes your mind off your troubles and helps tire your body out in a healthy way so that you can rest. Good luck to you.