My period has been irregular (off 3-10 days) for the past 3 months. before that i would always get it on the same day of the month. could there be something wrong?

Not terribly: It's doubtful there could be something really wrong with your cycles as it is not completely abnormal for women to deal with some abnormal cycles here and there during her childbearing years. As it has been 3 months in a row, however, a conversation an exam may be warranted with your family or GYN doctor about how to make them more regular if you are very concerned or if they bother you.

Not necessarily: If by "off 3-10 days", you mean that your start date varies by 3-10 days, there's nothing wrong. It's unusual that your periods usually starts on the same day each month. The orchestration of female hormones is complex and is seldom completely "in sync." If you mean that you're having a period all but 3-10 days each month, something is wrong & you need to see your gyno.