I know what I would do and that is book the first possible private transvaginal uterine scan I could get my hands on, even if it meant sticking it on a credit card.
As soon as you have the scan, you will know where you stand ie any fibroids, abnormalities and womb lining thickness. It's worth having that as soon as possible. I would ring round for an immediate appointment and if the NHS come up with an appointment in the meantime that is faster, you can cancel it.
It's always worth paying for peace of mind.