What does it mean if you got your period twice last month but not the next month?

It could mean a lot of different things. Since you missed a period this month, the first thing you should do is take a pregnancy test. If it is negative, you should call your doctor and see what they say. They may have you wait and see if you get it next month or they may have you come in and be checked. The second "period" you had could have actually been "implantation bleeding". This sometimes happens when the egg is embedding itself in the uterine wall.