Brief Answer:
you need to Visit your nearest ER at the earliest....

Detailed Answer:
Dear S, Welcome to HCM..
I've gone through your query and understand your concern..

Now this persistent nature of lower abdominal pain moderate to severe must be investigated thoroughly without any further delay..

I'm afraid that pain killers are only providing temporary relief, you must visit your nearest ER for a full body check up as well as appropriate and thorough investigations and management accordingly..

Now from your on-off history of constipation can be significant too..

Let me know are you able to pass gas or not, if not then it might be intestinal obstruction for which you must get properly investigated after hospitalization..

Also please let me know if there's any nausea/vomiting/fever ?

There are several possibilities(eg. Renal colic, acute appendicitis, faecolith obstruction etc.) to be XXXXXXX and exact diagnosis can only be obtained after thorough evaluation(CBC,LFT,KFT,Urine R.M, USG Whole Abdomen +/- CT Scan of the abdomen with or without contrast depending on the findings)..

Please don't depend on temporary pain killers and don't delay any further..just go ahead and get evaluated at the earliest..please don't try to drive on your own and ask for help..don't panic, as with timely intervention, it'll be matter of time till you get better..

Let me know how you stay in the due course..

Take Care
Kind Regards

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