I'm using nafarelin nasal spray twice a day in preparation for a fet next month. A few days ago I started experiencing similar symptoms that I'd get a few days prior to a period, lower back ache and now a dull ache low in the tummy area. Has anyone experienced this before? I did have northiserone to have a bleed, was on that 10 days. I've also had a scan to check the lining was thin enough and there was some fluid, I'm hoping when I start progynova that will help it go.