The Englishman, who has racked up four straight wins since joining the UFC, beat American Gordon by unanimous decision in the co-main event at UFC 282.
"I had to get surgery after my last fight. I hurt my foot in the first round, the first minute or two, threw a kick and hurt it. I felt it but cracked on and got through the fight," Pimblett told Sky Sports on Thursday.
"I couldn't get it looked at properly until I got back home. It was a lot worse than they thought.
"I had to get inner and outer ligament surgery, reconstruction. So it's big. I have already been on the crutches for six-and-a-half weeks, it could be another six weeks. I'll be lucky to fight this year."