What is wrong with me?

Hannah
Alright ladies I'm 5 days late for AF. Took a test this morning and there's wasn't even the faintest line. I'm never late, so if it's not a baby then what is wrong with me? 
Did any of you test negative for days past your missed period and then one day have a positive? Should I go to the doctor? 
Looking for advice, encouragement, hope... 😒