Clomid 50 mg didn't work.

Ch
Hi ladies. 
Background info. I started clomid 50mg June got pregnant but had miscarriage. 
I then took it again and it didn't work. 
The consultant is going to put me on the next stage which I presume is 100mg??
Has anyone heard or experience ovulation on 100mg when 50mg didn't work? I'm starting to worry that I'll never have kids
Thank you