had two periods last month (whilst on the pill) and have not

I am on Micronor (a mini pill, or prosteogen only pill) and have been since last Septmeber. I normally start my period on the 7th of every month, last month, I had my normal period on the 7th, and then another one on the 20th, which lasted four days.

I haven't started my period this month yet, and am not sure if I am late, or if I will come on a month after the second period of last month.

I take my pill at the same time every day, the latest I have taken it is an hour later (there is a three hour time in which you can take it and still be protected) and my boyfriend and I use condoms every time we have sex.

But, I am still worried about the lack of a period this month, i'm trying to decide if I am just being paranoid! I am quite the worrier and this is starting to make me get really stressed.

Sorry for rambling!