Blood clot?

So I have an old bruise about the size of a baseball. Its half yellow with a tiny bit of purple and the other half looks pretty much healed. Well right in the middle of the bruise there is the hard lump like the size of a pea. I can run my hand over the area and feel that lump with no problem. Is this normal?? Or is this really dangerous?? I'm pretty worried about it.... please any info is appreciated xxx