excruciating pains how long wil it last?

Hello everyone.
For 3 days now i have had the worst cramps of my life. Its on the up, middle left side of my belly. Its like my organs are full of inflammation and a knife it cutting in it. When the cramps occurs i have to lay down on ceramic floor and cant manage to not cry. Im usually used to disconfort and pain but this got me.
Went to the doctor yesterday told me probably my upper colon is flaring up. Ive always have my colitis in the rectum therefore never had bad cramps.
He put me on pentasa 500mg twice a day plus one salofalk enema. Plus he gave me omeprazole 20g once a day to kill the pain.
Have anyone experienced the same pain?
He said if within 2 to 4 weeks it doesnt work we have to look for steroids.
Im so scared i dont want to have the steroids as i heard the bad side effects.
Any thoughts on this?

many many thanks
its a difficult time.

well the doc think i might have extra acid. It is used as well for ulcers in the upper colon. I really feel its a weird pain. Ive had it once 2 years ago and had to go cold turkey with this pain for a month since all docs didnt know what it was. They left me on bad piles without numb meds too.
This doctor is new and he is concerned about my colitis flaring up hence the cramps.
If its not beter today or tomorrow he asked me to see him before week end. Thanks for your info if this doesnt work ill ask him what you took :P
This has to stop.