The midfielder has missed the club's last five matches having sustained a knee injury during the first half of the 3-2 defeat at AFC Wimbledon towards the end of August.
Collins was initially ruled out for between four to six weeks but his comeback was delayed further due to the 27-year-old's eagerness to get back to action ahead of schedule.
"There was a down spell where it looked like it would take a little bit longer (to recover), that still might prove be the case," Collins told the club's official website.
"I've made strides this week without getting ahead of myself and that's lifted my spirits.
"I'm back on the right track. It's a case of just working hard and following the instructions I've been given. I'm desperate to get back out there and in amongst it with the boys.
"As the gaffer said, sometimes I've got to be a little bit careful and make sure I don't overdo it. I want to have a massive influence on this season and the sooner I'm back the better it is for me to try and do that.
"It's looking a lot better this week, I'm happier about it and hopefully things will kick on from here."
Collins added: "To be honest, I don't know the timescale. The only thing I do know is that it's not going to be a long-term injury but there's no point at the moment saying two weeks or three weeks because it's one of those injuries that can be a little bit temperamental."