Valencia scored his third goal of the tournament to equalize the game in the second half and admitted after the game that he's playing with a knee injury since Ecuador's debut last Sunday.
"I had tests and it came out that I have a sprained knee, which is bothering me a bit. Today, I was already playing with pain but the important thing is that I was able to help the team and we are still strong," Valencia said.
The 33-year-old forward had a scan to see the extent of the injury before facing the second match of the World Cup but was declared fit.
Valencia, the World Cup top scorer after Friday's matches, went down near the middle of the pitch with under five minutes to full-time in the game against the Dutch team with trainers coming on the field to work on the striker's leg.
After the match, Valencia walked onto the pitch to congratulate his teammates on the draw.
"There is some improving [in the knee]. We hope I can hold it there and to have a good recovery in the next days to get in better conditions [against Senegal] and I to continue helping the team)," added Valencia.
After the match, Ecuador manager Gustavo Alfaro said Valencia was on a great spell but did not elaborate on his captain's health.
"He's a top-level player when he wears the Ecuador jersey. Sometimes he is criticized unfairly," Alfaro said, noting that Valencia is the only holdover from the 2014 squad that didn't advance from the group despite his three goals.
In Qatar, Valencia's goals in a 2-0 win over the host nation and a third to earn a point against the group-leading Dutch, mean a draw against Senegal on Tuesday will be enough to advance to the round of 16.
Information from Reuters was used in this report.