I have missed my last month periods... my periods are always irregular...
Need know if I'm pregnant?

If you don't know, we can't possibly know.

You probably should take a pregnancy test if you have missed a period.

So your period is a month late?

Try a home pregnancy test using first morning urine.

How late is the period ? If you are two or three week late, take a pregnancy test. Irregular periods make it hard to say, some women even miss a period now and then.