The Hornets registered their maiden victory under new manager Walter Mazzarri after overcoming an early two-goal deficit to triumph 4-2 in a roller-coaster Premier League encounter.
Deeney insists they felt slighted after Dimitri Payet set up Michail Antonio's second through a rabona cross, while Manuel Lanzini had attempted a shot using the same ostentatious technique.
"As a player I thought they were trying to mug us off a little bit," Deeney told BBC Radio 5 live.
"You can appreciate good skill and that was great skill for the second goal, but as a professional you cannot allow someone to do that to you.
"You see that in the playground with six and seven year olds and we are grown men.
"There were some harsh words said to each other and everyone had that fire in their belly again.
"We all dug in and started to lay a bit of a hand on them and before you know it we were getting more chances and we got two goals before half-time.
"I thought we were the only team who were going to win it in the second half."
Watford capitalised on an abysmal defensive display by West Ham to score goals through Odion Ighalo, Troy Deeney, Etienne Capoue and Jose Holebas - and they could have won by more.
The pick of the bunch was Deeney's inch-perfect lob of Adrian that punished a mix-up between the goalkeeper and James Collins.
It was Deeney's desire that underpinned Watford's comeback, leaving Mazzarri delighted with his skipper and his team.
"Troy Deeney showed that he completely understands my mentality that players must always believe they can win until the referee blows the final whistle, but he had that mentality even before my arrival," Mazzarri said.
"He has helped the whole team with his confidence and I think the whole team approached the game, especially after the first two goals, with the right mentality.
"The important thing that I'm looking at now is the way we play, and not the results
In previous games we deserved better results but unfortunately they did not come.
"Now we're doing much better and if we continue like this it will be a great turnaround.
"I'm happy with how we defended later in the game, but we also made some mistakes for the goals we conceded.
"After the second goal we woke up and in the second half we played a great game."
Slaven Bilic denied West Ham became complacent after building their comfortable two-goal lead, but admitted their defensive frailties must be addressed quickly.
"If we defend like this, we aren't going to win a single game
After the second goal it was confidence," Bilic said.
"Complacency is a question, but I don't think it was this
It was way too early for us to switch off, it wasn't like it was the 85th minute."
Source : PA
Source: PA