02 WRX will not always shift into first gear
So i got a 02 wrx and went out driving for a little bit today. A cold day of around 27 degrees. I was accelerating quickly and when to shift into second when my foot slipped off the clutch. There was a bit of grinding so i settled down and put it in 3rd. Later down the road i had to stop at a stop light and found i could not put it into 1st gear period. car off or on. clutch in or out. started going in second and got to where i was going.
I let the car sit for an hour to hour and a half and went to leave. It shifted into first just fine. Not really sure whats up that it would not shift when it is warmed up but will when it is cold. Any thoughts? Also is this something that should be professionally checked out?