So every once in awhile I’ll be sitting down on my couch and when I go to sit up and stand my vision goes either white or black and my head feels like it is being pushed in and I feel like I’m about to faint. I DO have a few different anxiety disorders and Angina Pectoris (chest pain). I don’t know if that has anything to do with it. I get migraines very often too. If anybody knows anything please let me know! Thank you