Hi. I Have Been Experiencing Right Flank Pain For 4

Hi. I have been experiencing right flank pain for 4 days now. It seems to come and go and is sometimes very severe. I did have a urinalysis 2 days ago and was advised by my drs. receptionist that it was negative for kidney/urinary infection but they could not follow up for several days so was advised to go to emergency if it got worse. I have suffered from IBS in the past and take dicetel 100 mg. 2/day and it seems to be under control. I did not have this pain before even when the IBS was at it's worst. Could this be IBS or another condition?