Welcome to HCM.
The kick that you received on your left testis, must have caused swelling of the testis as well as small amount of blood collection in the scrotum
, due to injury
to the testis and the blood vessels supplying it.
You have not mentioned when you got kicked.
Usually the blood collection is soft initially and later gets organised and is hard to feel and subsequently there may be cystic degeneration making it again soft to touch.
Veins crosing the scrotum is normal and you do not have to worry about it.
You have not mentioned your age. A condition called varicocele
can be felt as a bag of worms when you feel the scrotum.
It would be best if you could consult an urologist
and get a Colour Doppler Study of scrotum done, which should clear all doubts.