Hello Lisa,
It is very difficult to say what is going on in a "virtual consultation".
Does the pain that you are experiencing just in front of the thigh? Is it very pin pointed or it is more diffuse? Do you have this pain associated with any other disconfort elsewhere?
Did you feel any pull or tightness during the execution of the excercise at all?
Does pressing on the area create any trouble at all? Have you noticed a little bruise maybe?
There is anything that seems to alleviate your symptoms? such as putting ice or maybe having a hot bath?
What kind of gluteal stretching excercise do you do excatly? Is there anything else which seems to bring on the pain, like particular movement of the low back?
How the pain progressing since the onset? Getting any better?
You said that during the morning you are fine, when does the problem get a start again then? Any specific reason you could think of?
Would you mind to tell us a bit more about the problem you had in the past?
Thanks, all the best!