Summoned from the bench by Almeria's young manager Francisco Rodriguez to replace veteran forward Fernando Soriano with a quarter of hour left in the club's season opener, the 26-year-old Teerasil struggled to contain his delight at playing in one of Europe's top leagues.
"I was already happy when I was named one of the substitutes for the match. I'm delighted to see action on the pitch. I can't describe my feelings.
"I didn't know whether I was delighted, excited or nervous. It's a mixture of all but mostly it's one of satisfaction to get a taste of what we previously could only watch on television," Teerasil said.
Asked whether he was good enough to play in the Spanish topflight football, the Thai striker, who is on a season-long loan from Thai Premier League club Muangthong United, said it was too early to judge or make predictions.
"Let's see how it turns out. It's only one match so we cannot tell anything. There are still many things that I need to work on if I want to make more appearances or break into the first team. I need to improve on many things."
Teerasil said he was not satisfied with his form in a cameo role after Almeria failed to get their La Liga campaign off to a winning start by conceding a last-gasp goal to share spoils with Espanyol.
"I'm not concerned about my personal form. I didn't pay particular attention to how I played today. But, I'm unhappy because it could have been three points for us. When the team was not successful, I didn't have a reason to be happy," said Teerasil, whose side next faces Getafe on August 31.
Meanwhile, Champions League hopefuls Athletic Bilbao got their La Liga campaign off to a poor start as they were beaten 1-0 at Malaga.