It's a nightmare, really," he said.
"I'd just got my chance to play up front and I was buzzing.
"Being in the treatment room does my head in. I just want to be out there playing. It was a great chance for me to establish myself in the side.
"I have always wanted to play in the Premier league with Sunderland and now I'll have to wait.
"I was enjoying the Tottenham game but I knew it wasn't right when I landed badly after a header. I tried to carry on but I couldn't."