I I came on my period on the 13th of feb and come off on 5th of fen my periods normaly last 5 days I normaly get sore boobs before I come on and when I come off they go back to normal but this time they are sore and swollen I done a pregnancy test on the 11th was negative could I be pregnant ?

I may assume English is not your first language ?

Your dates are confusing, Came on period, 13 but off on the 5 ? That is going backward in time??

But if you had a period, no you are not pregnant.
Also you have to wait two weeks, after you miss a period, to test, so you can test perhaps the 1st of march and see what it says. ** always use the first urine of the morning, as soon as you wake up.