Blood clot from hematoma or scar tissue?

[CareyPrice31]

I had minor revision surgery on both sides to remove my incisions from underlying pectoral muscle.

I developed a hematoma on both sides and was told by the surgeon to wait three weeks to get them drained by a needle.

He drained them two weeks in and now I'm seeing him tomorrow to find out why I still have two hard lumps on both sides (not gland tissue), it's either blood clot or scar tissue.

How do I know if it's scar tissue or a blood clot? I'll ask him tomorrow but at this point I'm a bit suspicious because he didn't see the need to remove the hematomas with surgery and made me wait it out instead.