Harry Redknapp insists he did not resign as QPR manager because of the club's lack of signings in the January transfer window.
And the 67-year-old is already planning a return to football after undergoing knee replacement surgery.
Redknapp quit his post on Tuesday -- hours after Rangers had failed to land a number of targets on deadline day, including Tottenham striker Emmanuel Adebayor and West Ham winger Matt Jarvis.
QPR chairman Tony Fernandes accepted the former Tottenham boss's resignation after a 5:30 a.m. phone call -- a day after tweeting there would be "no more cheque book" as the transfer window closed on Monday.
Redknapp told the Daily Mail: "I haven't got the hump. We haven't had a row. I knew some while ago that we were not going to be able to get much done in January.
"We had one real target on the last day, Emmanuel Adebayor, because we are short up front. But he was too much money. I accept that.
"There are no hard feelings on my part -- I've not had a problem with Tony Fernandes in all my time there."
Redknapp added: "I know what people think -- that I've been sacked, or stormed off because we couldn't get the players in.
"My son Jamie said that my timing has to be the worst in the world. When I look back on my career, it certainly isn't my strong point but I can't control what people think."
Redknapp has been told he needs replacements for both his knees and the 67-year-old cited his health as a key factor in his decision to leave Loftus Road.
"I was awake all night, thinking about it," Redknapp said. "I'm struggling so badly now. I can't walk, I can barely stand and watch. I'm in pain all the time.
"I've been putting it off and putting it off but it has got to the stage where I cannot do the job."
Redknapp continued: "I went to bed thinking I would sleep on it, but then I couldn't sleep a wink.
"That's when I decided to call Tony. It must have been 5:30. I just told him he needed someone who could properly coach and manage the team in the next 10 weeks. It's such an important time. They need someone who can give it everything."
Redknapp was unable to save QPR from relegation in 2013 but led the club back to the top flight at the first time of asking last term.
QPR have been unable to carry that momentum into the current campaign, however, as they sit second bottom of the table with 15 games left.
"I was totally honest with Tony. I told him he needed someone who could commit to every aspect of the job in the next 10 weeks, and that's not me," Redknapp said.
"I still don't think I'm finished with football. When I've had the operations, I'll be looking for work again, I know that. I can't imagine my life without it. But right now, I've got to make my health the priority."