anyone out there who just quit smoking?

I quit a few years ago by going cold turkey, I started having panic attacks and didn't know why and figured it could be from smoking since i was having trouble breathing they lasted around 3 months and in that time I went to the hospital countless times for every test possible EKGS on a regular basis, xrays blood test pulmonary tests and more I was healthy as far as they knew and whatever was happening to me was mental. I asked a counselor at a drug rehab if what I was experiencing was some sort of withdrawal from the cigarettes they said possibly a little but it wasn't the main cause of the anxiety etc.