Nah..it is ok. Just slows the whole process down a bit which is not such a bad thing. Expect to take your time with steady thumb pressure. Hopefully you have a bigger gauge for pulling it up, or that will take longer too. I would warm my gear up under some hot water out of the faucet. Just set aside the time and you will be fine. You can pin anywhere that you want. Those 25's are great for delts and quads.
25g is what I use personally to inject, and 1" is the most versatile size that you can pretty much use anywhere. I would prefer a little longer for glutes, but it should still work fine at your bodyfat