I can’t be pregnant right?

I agree. Since you haven't had sex since your last period and you took a pregnancy test after having sex (which came as negative), then its probably just your period being late for some other reason. Periods aren't always regular anyway. Don't worry, just try to eat healthy though. And maybe go to a gyno if your period is unusually late or you completely miss it even though you're not pregnant (just in case, since sometimes cysts can cause missed periods too).

if you habent had sex then theres barely any chance of you getting pregnant maybe its just irregular because of your eating habits or playing sports often or other things

If you really think you are pregnant then take a test to ease your mind and give you a final amswer but I highly doubt you are.