I had my period twice in April in the beginning (4th-6th) and at the end (28th-30th). It is June and I haven't had my period since the end of April. I had intercourse three times after my last period on the 28th of May, 3rd of June, 22nd of June. I don't know what is wrong, why I even had my period twice in April, if I am pregnant or not, or if it's too early to check? What should I do ? Should I be worried?

If you haven't had your period since then take a pregnancy test first, then make an appointment with your doctor to get checked out for PCOS. That is Polycystic Ovarian Syndrome. It can cause irregular periods like you described. Do the pregnancy test first.

Are your periods normally pretty regular or have they been off before? May I ask your age? Do you know the usual number of days in a cycle for you?

Sometimes cycles are just off... can be age related (hormone changes), teens and older women may see more irregular cycles, could be just a brief fluctuation in hormones, could be due to hormonal forms of birth control. You can be late, early, or skip a month.

Other than when they showed up, were the periods in April normal to what you would usually expect... same amount of flow, lasting usual number of days?

Try a pregnancy test. If not pregnant, see if you have a period for June. If you skip another period, see your doctor.