Can Bruise On Knee Cap Cause Pain When Standing?

I was in a lacrosse game and I had a brake away and I pivitated wrong. My doctor told me that I had just sprained the ligaments and I had an MRI and it showed a brusie on my knee cap. I had about 5 weeks of therapy. My therapist told my that I alsoo hyperextended it and that I should see my doctor again. I see him this week. I just want to know what wrong with my knee. I have constant pain when standing, sitting pretty much doing anything.