What Causes Infertility Having Bloated Abdomen And Cramps?

Hi Doctor........ i had my period on sep 6 th.. den v had sex from 16th to 21st.. on 20th my stomach was bloated and for two days i had cramps.....den i felt tired for 2 to 3 days... later everythin was normal. i had back pain for about 2 days and today i got my period. am tryin to get pregnant for 3 months.please help me. Is there any problem with me