Ultrasound didn't go so well

Yesterday, I had an ultrasound done for my third trimester and to check growth of the baby as I am now 34 weeks 3 days but i have been measuring 3 weeks behind.

The ultrasound tech asked what my due date was, so I told them the date MY DR and the other hospital (I went into preterm labor at 32 weeks and was rushed to bigger hospital, and they measured baby to be right on track)

But this tech didn't believe me at all on my due date and seemed like they didn't know what they were doing.

They went by my due date and was concerned because of the percentiles the baby was falling under were low for some parts, so they kept changing to due date to justify and make the percentages better and make them feel better.

I said that they weren't suppose to be changing everything like that just because they didnt like the low numbers also if they would have taken the time and not RUSH AND HALF ASS it all and THINK. I said they were messing with the whole point of the ultrasound and its ironic how just 2 weeks ago baby was measuring fine according to TWO different hospitals and now all of a sudden he's not?

I have a dr app today and I'm going to inform him what they were doing and was messing with the results and basically messed up the whole point of the ultrasound and I'm requesting a new tech and ultrasound.