[Always *]

It can take a few cycles for your period and other stuff to regulate when you are using birth control. I would try it again and maybe try using a different brand/type - they all have different hormone's levels and mixes, some will work for your better than others. I found that some made it hard to lose weight, others I'd always feel a little hungrier and lost my sex drive, on another I always felt nauseous after I took the pill, on a final one I'd randomly miss my periods. For all the ones with draw back there were an equal amount of "bright sides". So, like I said, try again and give it a few months (unless your having extreme side effects).

With missing your period, yes, try the test again. If it comes out negative, you should still try your doctor to see if something is going on to cause irregularity in your period.