Experiences with Chlomid?

I just finished my first round of Chlomid pills from my doctor last week and when I came in today to do tests he said the pills didn't work and that I hadn't ovulated at all :/ Has anyone else had this issue? If so did upping the dosage help at all? He said they will up my dosage each month for the next couple months and see how things go. We've been trying since September/October and have had 2 relatively easy pregnancies before this one but I was diagnosed with PCOS recently and he said this could be a factor in why we haven't conceived.