Cant get enough air and dizzy

For a couple days I've been dizzy and slightly short of breath. Today I am super breathless and very dizzy. I went to the Dr yesterday and have to go back on Tuesday to discover why. I'm only 6-11 dpo so it's probably just me having an infection but I'm almost crying since I can't get any air. What can I do and what might this be? Chest doesn't hurt at all though. I just can't breathe :(