Hi!!
I too have the same problem... My surgeon says it is normal and everyone faces this. This is nothing but scab formation to protect our internal tissues.
Doc says it would go off in a few days time, depends on person to person.
Hematoma can be identified by discoloration of the area. Mine is normal.
Yes, it does feel wierd and hard, and pains when you try flexing your hand.
Hope it goes off soon. Try consuming antioxidants, vitamins, and gently massage the surrounding area with aloe vera lotion. This can help you heal faster.
Cheers!
KGR