The 18-year-old drove for both Red Bull and Toro Rosso during the young driver test at Silverstone earlier this month.
Sainz, second quickest in his first Formula 1 outing, said the teams were very happy with his performances.
While the Spaniard, who races in GP3, admits the test was a big morale boost, he is aware that he still has some way to go before he is ready to compete in F1.
"In January I wasn't even expecting to have a day in a Toro Rosso or even try Formula 1 this year, it was not in my plans," said Sainz.
"I'm a GP3 driver. I got the opportunity to test a Toro Rosso and a Red Bull.
"This is obviously a big boost for my self-confidence, and a spur to keep pushing in all areas, but I'm still 18 years old, I'm young and there is no way I will go to Formula 1 next year.
"There's no rush. I'm patient. I know that there is still a long way to go and that just doing a Formula 1 test does not mean I'm going to be a Formula 1 driver.
"I'm really calm about it and I'll keep pushing to improve."
Sainz, currently in seventh place in the GP3 standings, did concede he feels the test was a step in the right direction.
"I felt closer but still I have a really long way to go and a lot of work to do," he said.
"In total I've only done 60-70 laps in a Formula 1 car. I'm still very green. I've got a lot of maturity and a lot of speed to come from myself, and a big learning process.
"I hope another opportunity to test a Formula 1 car will come.
"I would really like it, because once you try it, it's hard to step out...to get a run with the Red Bull guys was like winning a big lottery.
"Formula 1 is my only dream and goal. My dream is to be a Formula 1 driver and maybe one day a Formula 1 champion. I'm even more motivated after the test."
- Motor Racing
- Toro Rosso