Glute pain after running

Looking for a wee bit of advice.

I have recently started up running (and swimming) in an effort to train for a 70.3. I come from a mostly road and track racing background with good time on the turbo and fast road riding. I have a good bike fit and was working into decent fitness.

About 10 days ago I completed a 7k run and immediately afterwards felt a tightness in my lower back and right glute (top of the butt). I put this down to just tightness and ramping up my mileage too quick.

This pain hasn’t really subsided. I can train on the turbo and swim well enough but walking and stairs in particular have me limping pretty well.

I attended a sports injury physio and we focused mainly on my lower back as this is whee I felt the most discomfort. My lower back now feels great but my glute is just as bad.

After a good stretching session I feel fantastic for about 15min before it stiffens up again. Also if I take paracetamol this masks the pain very well.

The pain is located as best I can tell deep in my glute above or around my piriformas. The physio commented on my TFL being tight. I have never experiance and injury or issue like this before.

Should I still be completing workouts on the trainer and swimming (I experience no issues after these workouts)

Should I be stretching and foam rolling? I do like a good myofascial release with the lacrosse ball but I’m worried about causing more damage.

Thanks

Were you able to find the answer somewhere outside?