Bullough said Friday that it was just the grind of camp and running back that has him banged up.
"Just a little bit of everything really," he said. "It's tough coming in at running back, you're not used to getting banged up that much. I'm just trying to get used to it."
Head coach Mark Dantonio wouldn't comment on an injuries, but did say it's part of camp.
"I don't talk about the injuries right now," Dantonio said. "Guys are going to be nicked up in the summer camp. Guy misses a day here or there, but there is nobody out for the season."
Bullough did participate in practice Friday, but didn't have pads on.
He said he would be fine to play in Saturday's scrimmage if need be.
"We will see," Bullough said. "If Coach D calls upon me, I am going to go in."
As for the tweet that created much of the buzz about an injury, Bullough said it was unrelated.
"It was just a bad practice," he said. "Stupid mistakes, things I shouldn't be doing as a running back. I need to get over the learning curve of being a running back. I need to be that guy and step it up a little bit."