Irregular Periods😑

I am 19 and have been having regular periods since I was 14. My cycle is always 25-27 days. I'm a virgin, not on bc, there's nothing about myself or lifestyle that is changing... and now for the last two months my period won't come on for 40+ days.. idk what to do or why this is happening. Am I the only one this is happening to? It doesn't happen to my mom or sisters... I'm so confused and scared there's something wrong 😕 I go see doctors soon but what if they can't find anything wrong 😞