Question about period/menstrual cycle?

Question about period/menstrual cycle?-ok, call me crazy for not knowing this but i think i'm either obvlivious to it or just misunderstanding something. to my knowledge, i was always told that the menstrual cycle is the same as the period. i get ovulation and all that other stuff, but what i DON'T get is...the cycle. now, my period usually lasts 7-8 days when i've read that cycles (period) usually are 28 days. is my period irregular because it doesn't go the full 28 days? OR is your cycle the first day of ovulation, the week of your period, and the last day of you ovulating? idk..am i missing the picture here?? someone help explain this to me!!

i'm trying to use an ovulation calculater and my only options are 22-48 days..i'm going crazy here

Okay so don't worry. You sound completely normal to me. A regular cycle does last about 28 days, but your period should only last between 4 and 8 days of the entire cycle. You should ovulate about halfway between periods. I hope that helps