Period maybe???

So on the 1st I thought I had my period but it was kinda light and didn't even last all day the following day. I had all the signs of it but got confused because it was reallly really light. Between that Friday the 3rd and Monday the 6th I had took a pregnancy test but it came out negative so I thought well Ill get it soon then. I'm now on week 5 from going off of my LMP and still havent started yet. Should I possibly see a doctor if it doesn't start soon???