unprescribed clomid

Hello, I am a very fertile 38 yr old woman. I have 6 children, ages 1,2,4,5,7, and a bipolar 13 yr old. I had a m/c in January and have actively been trying to get pg since may of last year.With just the m/c. I lost a set of twins in 04 and have not been the same since. I decided to order unprescribed clomid online, 100 mg and took it last month cd 3-7, O on cd 17 which I ALWAYS O cd 16 or cd 17, no pg. This month I took them cd 1-5 and am wondering how much this would increase my odds of multiples. I have already been pg with twins once, although m/c, I am advanced maternal age, I have been pg 11 times with 6 living children, I also used preseed and am somewhat overweight, but not obese by any means. Can you give me a realistic statistic on clomid in fertile women on clomid and what my personal chances would be???

Thank you in advance for any info you can give me.

Angi