It will be hard to answer the why since I do not have enough information regarding your period.
What I do not know is your age.
Or if you have ever started having a period? Maybe your friends all have theirs and you haven't had your first one yet.
Is it that You've had a period before and now you don't?
If you are a teenager, then a likely possibility is that you are having irregular periods which will happen for a while until you get older and your body gets used to the hormones that are trying to get you on a regular cycle. It can start regular and then go irregular, be shorter or longer than usual with shorter or longer gaps between periods and heavier or lighter flows. Its all normal and nothing to worry about.
If you are a young adult and your periods are not coming anymore but used to, something may have occured to throw off your hormones drastically and you'd have to see a Dr. for that..get your hormone levels checked and get a physical exam to see what might be causing this.
Good luck! [ Dragonflymagic's advice column | Ask Dragonflymagic A Question ]
Hardcore-Band-Geek answered Tuesday April 15 2014, 11:50 pm: Just going to state right now, You cannot get pregnant by kissing someone. Even if you where to swallow sperm, it would go into your stomach and be digested. You can only get pregnant if you had sexual intercourse. You're fine. [ Hardcore-Band-Geek's advice column | Ask Hardcore-Band-Geek A Question ]
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