Is this the reason im clastrophobic?

i have not gone to the doctor and confirmed it or anything, but i feel i am clastrophobic. i have a big fear of being locked in like an oven and burning to death or being trapped in the dishwasher and drowning. i know its stupid but thats how i feel. but i have been thinking, what could be the reason im clastrophobic? well, i was thinking, when i was younger, i was trapped in an elevator with my brother and sister for a couple of hours. i was only like 6 years old. also, several time i have been locked in the bathroom. the door just wouldnt open. i was goin crazy inside, i was alomost going to climb out the window. then last year in orchestra, my friend tricked me into going into a locker that is made to hold a cello. then she locked me inside! i was only trapped in for like 2 minutes, but i was still scared to death. could these be the reasons i feel so clastrophobic?