My periods are regular,last month it was about 4days early,this month i'm 5 days late is that normal?

No: It is not normal, but doesn't mean you are sick either. You might have some minor hormonal irregularities, but it needs to be investigated if the problem persists

Yes, most likely: Hi, there is individual variation in cycle length but anything in the range of 21-35 days is considered to be ovulatory, and therefore, normal cycles. So if your periods are on average within that range even if +/- 4-5 days, it's normal. The problem of anovulatory cycles (absence of ovulation) causes cycles to be really irregular and often >35 days.