I Am A 39 Year Old Female With A Very

I am a 39 year old female with a very stressful job and irregular eating and sleeping habits. Approximately 2-3 days ago, I was dizzy and the room was spinning for an extended amount of time (hours). I am not pregnant and was going to ignore it until I am having other symptoms that is making me wonder if it is more. I drove quite a distance and was outside in the heat and doing a lot of walking. I had plenty of water and non-alcoholic beverages. I experienced the worst charlie horse I have ever had and after walking/stairs, I experienced chest tightness, difficulty breathing, and heart racing feeling. I felt like I could not catch my breath, but with breathing techniques I managed to calm my breathing but still had the fluttered heart feeling and racing heart rate even after being in a rested position for a long period. This was not my brightest idea, but I drank a lot of caffeine (Mountain Dew) in order to make the long drive back home without falling asleep. I managed to sleep longer than my usual 3 hours and the racing heart and tightness is still there. I have a slight headache and the muscle soreness in my right leg where the charlie horse was. I don't have the luxury of going to a hospital at this moment, but was wondering if I should be concerned or is this just a fluke. At what point do I get concerned and have to seek medical attention and is there something I can do to alleviate these symptoms or prolong going to a doctor.