thigh looked like a bomb!! Can someone explain??

I've been on cypionate as per dr. At 1cc/200mg once every two weeks. I have actually been injecting 0.5cc every 3-4 days.I have been doing so for two months with no problems. Switching thighs and with every shot. The only pins the pharmacy had were 22, but gained some 25 from my Dr. I've been rotating between the two. Last night I was about to inject in right thigh with a 22, and as the pin was just about to the muscle, my thigh FLARED UP and then went neck to normal. Almost like it filled up with air. I tripped the +#$& out and withdrew the needle and held pressure. Nothing looked abnormal after. I went ahead and took the shot in the other leg with the 25. Any ideas wth happened?
Also, is water retention common with cypionate? Or maybe high protein and bcaa intake?

You hit a nerve. Quit freakin out. I have had my quad flare like that, i have let go of the needle and my leg spasmed and the needle laid down i have even had my quad push the needle back out. It happens. Steer clear of that certain site.

That sounds right. I'll definitely stay away from that spot. Thanks lol