No Temp Change

I am on my first round of Clomid 50mg, after my periods have been very sporatic.  I was on birth control for 10 years, and I'm 28 now.  I've been charting my temp each morning, but it has not gone up at all.  I'm on day 17 now and still waiting a temp change.  Doctor told me that my cycle should be 28 days and that I should ovulate on days 10-14.  Is it possible not to ovulate on Clomid?  My last period was 50 days, just to give you an example of how long they are.  My doctor is not doing any progesterone testing, ultrasounds, like others are.  I'm not sure why.  

Are some people's cycles longer than 28 days on Clomid?  Can I ovulate even in my temp doesn't rise?  How will I know.

I'm confused.....please help!  Thanks!

[Forum-M.D.-SP]

Sometimes there can be delayed ovulation on clomid, so I would keep testing. Also, probably 30% of women with irregular periods end up not ovulating in clomid, or require increases in the dose of clomid in order to ovulate. Thus, while clomid is a great first choice, it does not work for everyone. Regarding temperature charting, this is a good way of determining if you have ovulated, but not a good way of timing intercourse, since by the time you know for sure the temperature has gone up, it is too late and you have passed the fertile window. What I usually recommend to patients on clomid is the following:
1) use urine ovulation detection kits (they are like home pregnancy tests) that you purchase at the pharmacy, and test your urine every morning starting on around day 12
2) intercourse every two days starting day 12, until the urine tests positive for pending ovulation, then intercourse the day the urine first tests positive and the day after. If not positive by day 21, stop testing
3) testing for progesterone is not a bad idea, somewhere between days 21-25. If it is less than 10 nmol/l (Canadian SI units; same as 3 ng/ml in the USA) then your doctor might want to give you a course of provera to bring on a period and increase the dose of clomid.

Don't give up on this month yet. Since you are doing temp charting this month, give it 4-5 more days.