Dizziness, Pins And Needles In Arms And Legs. Brain CT And Chest X-ray Clear. Have PCOS. Due To Being Overweight And Smoking?

Hello, I m a 26yr old female. I am over weight and a smoker. I THINK I have an anxiety problem because I get so paranoid I ll get a migraine (I have not ever had one) that I don t want to leave the house. Anyway, for almost three years I have had dizzy spells. I suddenly get dizzy mostly in the afternoons but can occur anytime. I do not feel like the room is spinning, just my head. I get lightheaded, or a very heavy headed feel. I get pins and needles in arms and legs very quickly and sometimes get a tingly feeling in bizarre places like one cheek. I constantly yawn and have had a brain ct and chest X-ray which were both clear. I have been diagnosed with pcos and am not taking anything for that. Is it my weight and smoking? Or could there e something more sinister?