Continue clomid or iui? Your thoughts?

Mariam
 I'm 22 years old, been ttc for a year and a half diagnosed with mild pcos. I have 50 day cycles, but they are pretty regular .  did 5 cycles of clomid, ovulated on 4 cycles at 100mg but still not pregnant. I'm so confused at this point on what to do. I've read that the lifetime limit to clomid is 6 cycles. I'm starting to feel that clomid isn't ganna work (i understand that clomid did what its supposed to do though). I talked to my dr and he said since i respond so well to clomid that he wants to do a few more cycles before moving to <a href="https://glowing.com/glow-fertility-program">iui</a>. I'm just scared of doing more cycles. 
So what do u guys think? Should i stick with doing clomid or move on to <a href="https://glowing.com/glow-fertility-program">iui</a> ?
Also, my dr never mentioned me having other problems like endometriosis or fibroids. How are these diagnosed. Could the dr tell through ultrasound? Could i possibly have these?
Thanks.