Cat crawl update

Got to a benchmark in the very little crawl-specific training I have done today. Managed to do 30 minutes of solid circuits on flat concrete without any stops. My upperbody was feeling good from the shoulder conditioning i have been doing in the past and i had no problem with my abs or anything, although they were tight the whole time. The legs I think are the hardest part because they started to cramp a bit at around 25 mins, especially in the adductors and quads if fully extended. This meant i had to change technique from straight legs, to bent legs, to legs turning sideways and just alternating to stave off some nasty crampage. Felt good overall though and managed to crawl out of the car park down a flight of stairs when i had done the 30 mins without too much trouble. But when i stood up, damn did i feel dizzy, was really weird like i was floating haha, but it felt like a great relief. I didnt realise the amount of stress it puts through the knees though, as after about5 minutes walking back the patellar tendons in both knees really started to ache. Its because there is tension and force going through them the whole time and the legs dont get much range of movement so there is a lot of strain through the quads and consequently the tendon at the knee. Also pretty killer on the hamstrings and when i flexed my heel up to my ass i could really feel it was weaker.
Overall though quite happy with my progress on it. I think i could do 45 mins or maybe even an hour but it would be really hellish haha. Need to try and do this at least once a week and keep up the shoulder and core conditioning.