The Blues raced into the lead through Tammy Abraham in the 19th minute before the Anglo-Nigerian completed his brace two minutes prior to half-time to put his side on the path of victory.
But Frank Lampard’s men failed to keep the lead, allowing the visitors to claw their way back into the game through Callum Robinson and Kurt Zouma’s own goal.
Tomori is frustrated with his side’s performance in the encounter but has taken positives from the stalemate.
“We’re all angry because when you’re 2-0 up at home then the game should be safe,” Tomori told the club website.
“We said at half-time that we wanted to up it again but we didn’t do that. We conceded a goal really early on in the second half and it becomes very difficult when you do that. It’s disappointing but we just have to learn from it.
“This is Chelsea, we’re a big club and there’s a lot of expectations but we’re here to try to meet those expectations.
“There are high standards and when we fall below those standards then of course there will be questions. It’s not always going to be perfect but in games like today, when we’re in such a strong position and then we throw it away, it’s disappointing.”
“I’m here to try and push everyone else in the squad in my position so it was nice to get my full debut. I’m very proud but it would have been even better for us to get the win,” he continued.
“It’s what we’ve worked for all those years to achieve. Tammy and I have been here since we were seven and so has Mason, even though he’s the year younger than us.
“We’ve gone through the whole process and we’ve seen a lot of people come and go so to get to this stage is good but obviously now we want more. We want to really cement our places in the team and do big things for this club.”
Tomori will hope to start when Chelsea take on Wolverhampton Wanderers in their next Premier League game on September 14.