Recurring Physical Symptoms: Need Advice

About every week and a half to two weeks, I begin to feel "pins and needles" on my upper back and shoulders. the following day the skin on my forearms begins to feel like a mild sunburn. At the same time, my lower legs between the ankle and knees have sharp stabbing intermittent pain and throbbing. this generally lasts about 3 days then is gone for a week or two. At first my doctor suspected it was bacteria from my hottub, however I was on antibiotics all last week. and the "flare up" for lack of a better word returned. When this happens it causes my heartrate to increase and my blood sugar to rise.