Help? Mylan pill

So i have started my first ever cycle of birth control pills. I have the mylan brand that is a generic for loestrin or whatever. Anyways, my main question is, is spotting normal when taking pills? Like i had brown spotting early today and now it's more of a red color. I think i may have begun another period (2nd this month). But can anyone tell me how long spotting is supoosed to last? And what are some other side effects I should expect?