Doc gave me allopurinol during flare up

From my research, allopurinol should be taken either before or some time after the flare up goes away.

But after 10 days in agony and roughly 3 hours of sleep per day doc gave me allopurinol although my flare up is still active.

Im scared to start taking it so I dont get even worse pain..

Please help. What should I do?

Currently I'm taking indomethacin on my own but no effect from it so far.