What Causes Delay In Periods After Having Anal Sex?

Hi ma am,in february I took deviry 10 mg tablet for irregular menstruation and in march i got periods and after my periods i have anal sex with my boy frnd(my first time sex )and this month (april) I dint get my periods. Its means I am pregnent? I read some blogs from google . Anal sex will cause to pregnancy. Please advise I need to take pregnancy test or can I wait?