Taking to Twitter, she wrote: "I could not hold back my tears when I saw the Indian flag ???? and heard the National anthem playing. Words can't express my feelings about yesterday's win at the World Championship. Had been preparing for it for so (sic)."
Sindhu's gold is the second medal that India won at the Worlds this year with Sai Praneeth winning a bronze in men's singles category.
The last time Sindhu and Okuhara met in a World Championships final was in 2017. In a pulsating encounter that lasted nearly two hours and involved a 73-shot rally, Okuhara emerged victorious in the end. Sindhu again reached the final in 2018, only to go down to Carolina Marín of Spain. However, she finally broke the jinx this time, brushing aside her opponent with a dominant show from start to finish.
In stark contrast to Sindhu, the Japanese World No. 4 on Sunday looked completely at sea against the Indian star's relentless attacks.
Sindhu dedicated the historic triumph to her mother, who celebrated her birthday on Sunday, and the country.
"This means a lot, it is a big win. I had lost in the finals in the last two editions," said Sindhu in an on-court interview after the match.
"I won for my country, I am really very proud," said an emotional Sindhu wearing a satisfied smile on her face.
"I would like to thank my coach (South Korean Kim Ji Hyun) and Gopi sir (Pullela Gopichand) and also my parents. Today is my mother's birthday, so happy birthday mom!" she added.
( With inputs from IANS )