Is it normal to have a firm lump next to nose one month after sinus lift surgery with implant?

I had sinus lift with bone graft. Two implants were placed at the same time - one on 25 (which didn't need bone graft) and 26. After the surgery my face was very swollen and severely bruised. One month later there is a hard lump above tooth 25 next to my nose which is changing the shape of my face and alters my smile. There is no pain and my nasal passages seem clear. Is this normal and will this lump go down? The dentist said he had to place extra bone than originally planned. Could this be the cause?