What Causes Headache, Shortness Of Breath And Dizziness?

Hi, I am a I am a 37 year old (I thought fit) male. :-) I have reocurring throbbing at the back of my head (mostly on bottom right side, but sometimes on equivalent bottom left side) which I used to get rid of by vigorous exercise. These throbbing headaches was accompanied by cloudy thinking etc. Recently my glands on either side of my neck and the base of my skull at the back have come up and also some lumps have appeared on the front left side of my neck and the rear base of my skull. Also very rarely (few times a week) I experience shortness of breath out of the blue...usually when talking which is accompanied with dizziness. Any ideas?