@wittyBlackberry4568 that sounds pretty scary :( how are you doing now?
If you pass out from anxiety, find a safe location to sit or lie down. Take slow, deep breaths to relax. Stay grounded by focusing on your environment or physical sensations. Inform someone about what is going on so they can provide assistance. Drink water gently to stay hydrated. If this occurs frequently, consult a mental health expert. Remember that it is typically not dangerous, so focus on self-care and support...
I get Pseudo-seizures caused by anxiety and have come close to passing out. I'm not a doctor so you may need to verify my advice with one, but I recommend potassium and a small lightly sweet snack such as a cookie. Potassium helps to calm and the sugar will give you dopamine. My doc has me carrying around applesauce pouches for this.