are you new to this? what do you expect with a 400 concentration ?? test 400 is going to be painful and certainly can leave you with bumps and PIP after injection... thats what you get when you use concentrations that high
Most likely it's either due to the high concentration or the fact that you used a slin pin in your quad when injecting not getting it deep enough. That's harmless and will go away.
If area around the lump gets red, starts swell and/or give you a fever you got some bacteria in there. Do NOT try to squeeze it, if it doesn't pass on its own fairly quickly, go see a doctor.