You could have easily done that with a 5/8. However even when you hit muscle a certain amount comes back out of the depot and flows down due to gravity. I've even gotten sore spots lower than the injection site with my prescription cyp when I first started trt. Keep watching and if it doesn't improve for sure see a doctor. My experience with pip like yours is it won't totally be gone for about a week. Unless you want to be crippled for the duration of your cycle you best be getting some GSO to cut it with. Mix in the barrel until you find a mix you can tolerate. Even then the pip can be worse then normal cyp 250 due to the amount of EO, BA, etc they use to suspend that much compound.
Live and learn bro.