How many weeks?

hello po, last nov 18 nagspotting po ako then nov 20 nagregular mens. po ako, dec 18 regular mens. din po then this January delayed po ako,1 day plang po ng missed period ko nag p.t na po ako and its positive.i tried again on my 2nd day of missed period and positive din, mga mommy patanong nman po kung ilan days/weeks na ang nsa tummy ko, salamat po. my first @ 28?