Hold up I'm confused

Jayzlynn • I`m 24 years old and a mother to a little boy that was born September 15th 2016 name Elijah married now
Ok so in June I had a chemical pregnancy bleed for awhile and then I guess everything was back to normal but then last month I guess I thought I was gone get my period on the normal day the 23rd like I do every month but no it came the 30th and lasted to the 1st of this month my periods have always been only 3 days and it's usually a 30 day cycle but Glow got me this month that my period is not due till sept 5th and idk if that's right or what Can somebody help me please!? Cause I am kinda having some pregnancy symptoms