Am I pregnant if I have 2 menstrual cycle in 24 days?

Not likely. Typically it is the absence of menstrual cycles that raise the concern for possible pregnancy. If you are young, irregular cycles may be common. If new after having regular cycles may lead you to see your doctor. In some cases we can start you on birth control that helps regulate your menstraul cycles. This should not be done, however, without having a pregnancy test first to be safe.
Not necessarily. If those two periods were full flow and not "spotting" and this is your regular cycle interval then, no you are not pregnant. However, implantation bleeding or "spotting", sometimes presents as a 2nd "period" and can indicate a tubal (ectopic) pregnancy. If you are unsure, please see a md and/or do a home pregnancy test.