Question ladies

So i had about 6 ultrasounds for two in the beginning of Aug they only saw a sac. 8/16 tech found a very tiny pole and hb of 90 he said heart just started out i got the due date of April 10th 2018. On 8/23 i was 7weeks 1day hb of 108. On 9:6 i was 9weeks 1 day hb around 180. Then at my final scan 10/4 i was 13weeks 1day. They were all transvaginal except my 13 week scan and stayed right on time together.

I was told they could be 5-7 days out then i heard 2 weeks, would u think by now after all those being right on i would have to worry about that ?

Im 14+1 today!

And also my LMP was june 27th but ultrasounds are saying july 4th. Why?

( had all those u/s cause was rough in the beginning plus miscarriages in the past sorry if im paranoid )