The Reds have picked up just six points from their opening six games and are in 16th spot in the Premier League.
“Six points from our first six games is not what we wanted,” Reina told the club’s official magazine.
“People who criticise us about it should look at the fixtures we’ve had. It has been a difficult start. Arsenal at home and then going to play Manchester City, Manchester United and Birmingham away was never going to be easy.
“Not many teams will go to the City of Manchester Stadium, Old Trafford or St Andrews and win. Those three teams have very good records at home.”
Roy Hodgson took over as new manager at Anfield over the summer.
“When you have so many changes moving in a new direction under a new boss, things don’t happen instantly,” added Reina.
“It can take between three and six months before you see improvements. Obviously the quicker we adapt and improve as a team the better it will be for everyone.
“That doesn’t just happen overnight. Each of us has to adjust to working in a new way.
“With the passing of each day I get used to it and what the manager wants. It’s the same for all of us. We need to be patient.”
