Hi 'injuredunfortunately', and thanks for your post. It does sound like you perhaps over did things a little but too much, too soon perhaps. 90mins of walking on a treadmill whilst trying to play with a PS4 gaming device would be a challenge for someone trained I think. Are you using a hand controller whilst doing this? It is possible that the reduced or altered upper body movement that is required to play the PS4 has mean that your leg/pelvis/low back motion has also had to alter as a response. This might have 'stretched' a few structures more than they are used to, especially over a 18 month pandemic and reduced activity. As for what specific structure is causing the issue is hard to say but it does appear that there is some referral of pain to several areas, which might well emanate from the culprit (even in the absence of discomfort in that structure). Your initial area/s of discomfort would more likely point to the original issue. It could for example be an inguinal hernia strain. And part of a treatment approach might be to look at the non-painful side to see if there was some movement restriction on that side, which then led to an overuse on the now symptomatic side. Those can take a long time to fully resolve. My advice would be to go and see someone to assess you as a one-off session for advice. I don't think using the internet as a trial and error service would help for a fast recovery. Work out exactly what the issue is and then the internet is full of ideas on exercises and other ways to help work towards normality again.
Let us know how you get on.