The 31-year-old opened the scoring at Southampton and provided the pass from which Romelu Lukaku doubled the Baggies' advantage.
However, Fortune saw his game come to a premature end after angrily confronting Gaston Ramirez for an elbow on Shane Long.
The Saints man also saw red and West Brom went on to win 3-0 thanks to a late Long strike but Fortune was downbeat after the game, apologising for reacting as he did.
"We won 3-0 and I scored and got an assist so it was a good game for me and for West Brom, but afterwards I know everyone will talk about my red card," he said.
"First of all I want to apologise because I don't usually do that. People know I'm not a bad guy so I am really frustrated but I just reacted to what the Southampton guy did.
"I would just like to apologise.
"He is my team-mate and I am really good friends with Longy and when I saw that I just reacted.
"I know it's not a good reaction but when things like that happen you are just angry.
"I talked to the referee and said I am not like that and it's my first red card in four years.
"I hope he will report that to the FA and they're not too hard with me because I don't deserve to stay off the pitch for too long."
The red card means Fortune will be banned for three of West Brom's four remaining games.
With his contract at the Hawthorns set to expire this summer, he hopes yesterday's game was not his last for Steve Clarke's side.
"For the moment I am still waiting for something from the club," Fortune said.
"The fans ask me on Facebook or other social media but I always answer that I would be really pleased to stay here and I am just waiting for the offer from the club.
"Now it is up to them and I am still waiting.
"I talked with the manager and I said if he doesn't want that to be my last game they have to sign me.
"I think I have done well in my three years here so we will see what happens.
"They know my position. I want to stay and if the club want me to stay we will have to discuss it, but it is up to the club."
West Brom boss Clarke suggested after the game that no decision on Fortune's future has been made.
That is a decision he will make at the end of the season as for now finishing strongly is his only objective.
"I just feel we had lost a little bit of focus and momentum in this season, which is why I said in the last press conference that I'm not really interested in next season - I want to finish this season well," Clarke said.
"Southampton was the first step on that and we've got four more steps to try and make it a season that everybody can look on with a little bit of satisfaction. We've still got four to go so there is a possibility of more points.
"We've got two games at home and away so we'll try to get as many points as we can and try to break the 50 points barrier and see where we are in the league."