Dale Earnhardt Jr. reportedly had undiagnosed concussion at Kansas tire test

The news today that Dale Earnhardt Jr. will miss the next two NASCAR races due to a concussion sustained at Talladega left everyone wondering if they missed signs of a head injury after Sunday's race.

It was a bit surprising to see Earnhardt Jr. wincing and rubbing his head so much after crashing at Talladega, but the driver twice said he was OK when reporters asked how he felt.

"Yeah, I mean, I just took a lot of hard shots," he said then.

While he seemed a bit out of sorts during the interview, it appeared to be more of an emotional reaction than the reaction of a man who had just sustained a concussion. He wasn't spacey or distant or any of the signs you'd think would be associated with a head injury; rather, it seemed he was just disgusted with restrictor-plate racing – which is exactly what he said.

I still wondered, though. So during a phone interview with Earnhardt Jr. on Tuesday, I brought up the topic again.

"It just looked like you were holding your head," I said. "But you feel OK?"

"Yeah, I feel fine," he answered, with as normal of a tone as someone could have.

Clearly, though, he didn't feel fine on Wednesday – his 38th birthday. Earnhardt Jr. went to the doctor, where he was diagnosed with a concussion. On medical orders, he will miss the next two NASCAR races at Charlotte and Kansas (Earnhardt Jr. was never examined after Talladega because he drove his car back to the garage).

In fact, the Associated Press reported this morning Earnhardt Jr. also sustained another concussion when he crashed during the Kansas tire test. In that respect, this was Earnhardt Jr.'s second concussion in two months – and that's a big concern for NASCAR's most popular driver.

Earnhardt Jr. is set to address the media at 11 a.m. Eastern time, along with team owner Rick Hendrick and crew chief Steve Letarte.