The only times my period has ever been late or off was when I took the morning after pill and the few times where I was EXTREMELY stressed out. So yes, stress can definitely make your period late.
That being said so can weight changes, hormonal imbalances, vitamin deficiencies, too low or high BMI, illness, etc. The list is pretty long. So if it gets to the two week mark, you may need to see a dr, just to rule out anything serious. Other than that, if you haven't had unprotected sex in the past several weeks, I doubt you could be pregnant.
Oh ok thanks 4da advice, but does stressing & worrying really cause ur period to come late? Because I havn't gottn mine & I was suppose to get it a week ago , culd it had been caused frm my stress or culd it be something else ?
Sperm really needs a way to reach the egg. Even if he ejaculated on your underwear I think the possibility would be slim. It's really difficult for sperm to make that track without some help-not theoretically impossible- just not probable. I would suggest not to worry. Stress can cause your period to be late and can make you pretty sick (throwing up, headaches, nausea kind of sick).
In the mean time, get a hold of some birth control. It sounds like you're on the verge of becoming sexually active and you need to make sure you're covered. However, no birth control is 100% effective and most pills have to be taken every day without fail. So make sure you have some back up- It a good idea to have condoms in your room or on your person. Just make sure they're in a place where they won't get rubbed a lot (like in a wallet) because that could damage them. Always remember only a condom can stop a STD, and because condoms and birth control do sometimes fail- doubling up is the best way to prevent against a 7lb ooops.