My last period ended 3rd of July and I had sEx from th?? 15th through 23rd of July!my montly cycle is 28days!on th?? 24th I started having th?? Symptoms that my mentual period is coming but I have pains at my lower back,headache and urinate often than before!could I be pregnant

Yes, it's possible you could be pregnant. However, you are going to have to wait to see if your period comes when it is due. If not, test using first morning urine.

What if the period comes!What do I do next!

What if the period comes!What do i do next!

Then you probably aren't pregnant. ;)

If the period comes them most likely you are not, very rare to be pregnant and have a regular period