lump on testical

hi im 16 and about 14 weeks ago i found a small lump at the very tom of my right tesical it seems to be the size of half a bb and seems to be hard. I went to the gp twice in the same week of fiding the lump but he could not find it so i waited for 10 weeks to c if the lump would go but it did no. So i went bak and he hase put me dwn for a none urgant ultra sound which meens i have to wait about 14 weeks i hav 8 weekd waiting time left. I have jst recent noticed tht the lump seems to click form right to left somtimes and it seems to be white when i push it up to the skin my dad and mum are both mental helth nersis and they tell me that the lump might be just a cyst or a calcium lump but im not sure. Also when i found the lump i was experiancing pain in my right bum cheek and in the right testical i am woried that i have tc and becouse it hase been goin o now for so long would it have spread to other part of the body like the lynth nodes.