I'm late!

I am 4 days late! The first day I felt all the symptoms of being on my period but no sign of it at all the second I felt the same as well but nothing. I took a pregnancy test but I guess it's too soon to tell with them bc it said negative so I will take another one at the end of this week. But does this sound like I could be pregnant? I've never been pregnant before. My sister is now and she said all the symptoms I described to her is exactly how she was before she found out she was pregnant.