Post iui cm

I had my first iui yesterday and today I am having a lot of watery cm. The midwife said I would have some spotting, but she didn't say anything about cm. I had a positive opk yesterday and normal, fertile cm. Today its been more than I've ever had after ovulation, and I had a very obvious negative opk an hour ago.

I don't take any fertility meds.

I couldn't find anything useful about it on Google, so I was wondering if anyone here has experienced the same thing. Mostly I'm hoping it's a good sign.