CD17 & Clomid

TTC with PCOS. I've had 3 IUI'S on Clomid, trigger, and progesterone. Getting ready for a fourth IUI. I had a rescan today, CD17, and I only have 1 potential follicle on the left measuring 10. I am worried because it is late in my cycle and I am no where near ready to trigger. For my previous IUI'S I have only had one potential follicle but I have been ready between CD16-19. RE says not to worry yet, rescan in 5 days. Anyone else share a similar experience while on Clomid? Anyone have any tips on how to help that follicle grow?