What Causes Lightheadedness, Spot On Tongue, Muscle Spasm And Cramping?

Hi, over the last few days, I've occassionally felt a little lightheaded at odd times. Also had a white tongue with the odd spot on it over the weekend which appears to have gone back to normal. If I breathe in very deeply, I can feel a tightening in my chest (I'm sure I'm inventing symptoms now!). Also getting a few muscle spasms and a tight feeling in the muscles in the forearms near my elbow and cramping up quite easily. I sound a wreck but actually I'm usually very heathly. I often have yeast type ailments and put the mouth down to that again this time with some sort or oral thrush etc. Should i be worried?