. My girlfriend had unprotected sex with her boyfriend 17 days ago. On the very next day she stated she was having symptoms of pregnancy. Every since that day she has complained of lower pain, peeing more and other pregnancy symptoms. She does have the injection I'm planted in her arm which has been there for a year since her last pregnancy. She refuses to take a test stating she is scared. My question is can she be really pregnant already and feel symptoms the very next day less than 24 hours after sex?

No, she wouldn't feel symptoms the day after sex. She could, however, be feeling some at this point if she were pregnant. It would be unlikely that she is pregnant having the implant, but it can happen as no form of birth control will be 100% effective.

Being scared isn't going to change whether she is pregnant, and IF she happens to be, she certainly needs to find out. She should see what happens when her next period would be due. If she doesn't want to wait that long, she could ask her doctor about having a blood test done sooner.

What she may be experiencing are symptoms of a bladder infection and that too should get checked by her doctor.

Her period she stated was due on the 14th of this month but she said it hasn't come yet.

Have her give it a few more days and see if it shows up late, which can sometimes happen. If no period still, then she should try a pregnancy test or see her doctor.

Did she have sex with you, or anyone else, prior to the sex with her ex 17 days ago?

Her period she stated was due on the 14th of this month but she said it hasn't come yet.

She has sex with someone at the end of August or beginning of September. She said the condom slipped off by accident.

All her symptoms can be explained by other means. When was her last menstrual period? Was it the 14th-ish of October?

She needs to wait about 10 days and take a pregnancy test if she doesn't get her period. It could be stress that's delaying it, or it could be pregnancy. If it is pregnancy it would be almost impossible to tell who the father is.

Yes it was about the 14th of October. I appreciate your response and thanks for the information.