The 18-year-old had secured pole position in F2 on Thursday when he was given the call up to replace Carlos Sainz, who had been diagnosed in appendicitis on Friday morning.
Speaking with Sky Sports F1 after the session, Bearman reflected on his debut appearance in F1.
"I woke up preparing and mentally thinking about my F2 race then I got chucked in the deep end for F1 FP3 and qualifying,” he said.
"Of course not the ideal situation and I feel sorry for Carlos and wish him the best but it's a fantastic opportunity. A bit disappointed with everything but it was a fun day out there."
When asked about what the biggest change is from F2 to F1 machinery, he added: "The fact the track evolves so much. We did F2 qualifying quite early in the weekend and the track develops a lot.
"The grip level is just incredible. After my first lap, I was shocked. In F2 you drive on the limit of the car. In F1, it's the limit of the driver and what the driver is prepared to do.
"That's a great feeling but it takes some time to get used to."
Bearman was very apologetic over the team radio after Q2 following a couple of slip ups during the session, but stated that he will feel a sense of pride over his achievements down the line.
"At the moment not so proud, the racer in me knows that the car was quick enough to be in Q3, so a little bit disappointed with that,” he said.
"But I know that when I look back in a couple of days I'll be quite proud of what I've managed to do today.
"The goal was to do as many laps as possible. Especially at night, I missed FP2 which is not ideal. That was the goal.
"The soft tyre lasts quite well, it's quite durable, so just tried to get as many laps in Q1. Q2 was a bit more messy, a few mistakes on my side, so that's where I'm disappointed."