Letrozole dose?

Hi,
I have been doing Letrozole for 2 months so far. 
First month was on 2.5mg and nothing happened (was away so couldn't get ultrasounds) 
This month same dose and had one big follicle on day 14 and doctor said that it was ready but then it didn't happen till day 20 and said that it shouldn't have been that long so I'm not holding out much hope for this month. Next month we are doing an <a href="https://glowing.com/glow-fertility-program">IUI</a> and he also said I can double the dose but also mentioned that if there are too many follicles they will cancel the cycle and that's freaking me out! I've waited so long I don't want to have cancelled cycle. 
Anyone on here upped their dose and got more than 3 follicles?