The 26-year-old medium-fast bowler snared three wickets for 27 runs from 17 overs and supported Dwayne Bravo to help West Indies restrict India to 235 for nine after the visitors chose to bat on the first day in the opening Test on Friday at the Antigua Recreation Ground.
Collymore underwent surgery last November to remove a bone spur in his right knee tendon.
"The injury was worrying, but I was glad for the rest," he said.
"I was missing in New Zealand, but I came back and redeemed myself against India and I was happy with my performance.
"I'm happy with the number of overs I put in. There are lots of bowlers in our side. About five or six guys bowled. All in all we had a good effort to start off the series."
Collymore's return to the longer version of the game was almost doubtful, after he twisted his ankle in the final One-Day International against the Indians on Sunday at Port of Spain.
He passed a fitness test on the eve of the Test and helped to contribute to India's misery on a pitch that offered the West Indies bowlers considerable bounce and movement.
"The surface in Antigua usually favours batsmen, but I thought the pitch was seaming a bit in the morning period," Collymore said.
"I thought we bowled well, but we could have restricted them a bit more. We need to get the final wicket early on Saturday and, hopefully, bat India completely out of the game."
West Indies wicketkeeper Denesh Ramdin was also pleased with his work behind the stumps, after he had been dropped for all but the last ODI against the Indians.
"The brief rest I had did me the world of good," said the 20-year-old Ramdin, who held three catches in the Indian innings.
"I went home and worked on my game, and I think I am keeping much better than I had been in recent matches. Taking the catches I did also helped to boost my confidence and I am looking forward to the rest of the game."