Bruised Knee

Hi, I was paying basket ball about a month ago and landed heavily on my knee.
I went to hospital but they said it was only bruised.
I play football twice a week and each time since then I hav either being knocked or fallen on my knee and recieved alot of pain. But last week I clashed with someone else’s knee and my knee swelled up.
I now get pain from bending it and walking.
I don’t think this pain will ever go away! some advice would really be appreciated.