I had a routine 16wk checkup this morning, BP was normal, left and got something to eat, stopped at a store and then Publix on the way home. Got out of my car and started walking and got a very heavy feeling in my chest-like when you can feel your heart pounding- and got very dizzy and fainted in the parking lot. Luckily my husband was with me and had me so I didn't fall, but he said my knees buckled and I went limp in his arms. I came to within a minute but was so scared, I felt fine afterwards except for a small headache. My Dr said they call it "vague-ing" out. (Vasovagal) And that my hypothyroidism could be a factor.