The 35-year-old has been an instant hit at Old Trafford, since he arrived last summer as a free agent from Paris Saint-Germain, scoring 26 goals in 41 matches.
However, his one-year contract expires at the end of the season and he has been linked with LA Galaxy.
In an interview with BT Sport, Ibrahimovic said: “I came here as a 35-year-old. Everybody thought I was in a wheelchair. What happened? The lion is still alive and that’s the way it is.
“I have proved what everyone has said is wrong.
I don’t hear the talk anymore, it is not fun anymore, because the haters became like fans and even like believers.
“I am 35, 36 in a couple of months, which is proven as just a number. I keep going and make the other one look older than me.
“I know the Premier League is begging me to stay. I came here, I said I needed one year and it took me three months, what I wanted.
“How I feel today, I don’t know if I will feel like this next year.”