clomid

I'm on CD 21 after taking clomid on days 3-8. I'm craving weird foods and have a belly like I'm pregnant. I took an opk on CD 20 and it was really positive,but I ovulated literally 8 days after taking the last pill. I took a test and it was bfn so when should I try and take another one? And what are the chances that the opk test was right and i am pregnant?