The SPL newcomers suffered a 2-0 defeat at Fir Park, with first-half goals from James McFadden and Chris Humphrey ending County's Europa League chances.
Brittain, who has signed a pre-contract with St Johnstone but publicly said he wants to get out of the two-year deal, was stretchered off after falling awkwardly as he tried to tackle Humphrey.
And Adams said he was unsure of the extent of his injury, and also refused to comment on the midfielder's contractual situation.
"I am not sure, he is away to hospital now. I am not sure the extent of his injury, we will see," the County boss said.
"I don't know what's wrong with him and we will obviously assess him when he gets back.
"He is away to hospital, don't ask me another question, he is away to hospital."
Adams also refused to be down heartened by the defeat at Fir Park, despite missing out on a Europa League spot.
"We have had a fantastic season. Our main aim before today was to finish in third place because we played our way to that situation, but the main aim at the start of the season was to finish in 11th position," he said.
"We finished in the top six in our first season in the SPL and we are one of the best teams in the SPL this season and I think a lot of credit has to go to the players and the backroom staff.
"We are Ross County football club, we are a wee team from the north and we have finished ahead of Aberdeen, Hearts, Hibernian, St Mirren and could finish ahead of Dundee United, so we have had a fantastic season."