It sounds as though the pain in your back and glute is not too extreme. How far into your cricket season are you? How many overs are you bowling weekly? Did you have a good preseason training?
I have not bowled regularly since February 2011 when I felt myself tweak a muscle in the lower right back and right leg which turned into a constant ache in life. I was ill with cancer of the chest from April-September and had a couple surgeries and a fair bit of chemo. I tried to bowl again in December 2011 (the pain faded somewhere around August) and was very weak but could bowl without discomfort. A couple days later, the ache returned.
Basically, every day, there is an ache somewhere in my lower right back or right leg. The ache is usually in a slightly different place each day but it is always there in some capacity.
I think that while I have an ache just in everyday life, I shouldn't really be trying to bowl so I spend my time trying to work the core, stretch the glute, stretch the hamstrings, stretch the lumbar back so that the pain can be relieved but nothing has been successful.
Just under two months ago, on a day where the ache was low (but still there), I did a massive amount of stretching at home, went to university nets, bowled 20 minutes of very slow spin and then moved up to medium pace and eventually to 90% full tilt. The muscles were getting used to things but it was okay. However, after about 20 minutes, my back just decided to gradually stiffen up completely, so I bowled some more spin for 15 minutes and went home.
I'll tell you now though, I have to warm up so incredibly slowly that it will definitely make you laugh. I begin with spin that honestly a 10 year old will be able to dispatch because initially, my back just doesn't allow anything else.
For example, I cannot currently even imagine playing a game because if I am unable to bowl in the nets my slow spin for 20 minutes immediately before the fielding innings begins, I will simply be not able to bowl anything resembling cricket. Also, I feel that even when warmed up, something is stopping me from fully slipping myself into full gear.
Thanks for engaging with me, though, mate. I've seen a lot of physios and none have been able to help me and I had an MRI which frustratingly came out clear so I have no clue what is wrong. Probably something muscular but then why have no physios been able to fix it.