Worried about thickened womb lining

Hi all, just had an ultrasound and transvaginal too. The songrapher said womb lining was thin at first and then it was thick at 8mm so need further tests. He did say it didn't look like suspicious thickening (?) but I need biopsy. I'm worried by what I've read about biopsy experiences but also wondering if anyone else had been given similar info and what happened. Thanks.