Hello and welcome to HCM.
Thank you for your query.
First of all, as you have been prescribed
clomid, which is usually for the treatment of PCOS/
PCOD in women who are trying to conceive, your cycles would have been irregular even previously. But, do not worry, periods can change their normal regularity while on clomid.
But, more importantly, your symptoms of abdominal cramps,
back pain and brownish discharge are more often seen together in women who are soon expecting their period. As yours is the case, the likelihood of these symptoms being due to an approaching period is higher than due to the medication clomid.
Only if these symptoms persist even after you are done with your period, should you be concerned and take it up with your doctor, until then, you may rest assured.
I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you.
Best wishes.