The 22-year-old first suffered the injury in September and was unable to feature again for the first team until last month's clash against Chelsea.
But he then aggravated the problem in the 1-0 win over Aston Villa, although he is confident of being cleared to resume training next week.
"It's just over two weeks into my injury now and it's healing well, I'm hoping for maybe another two weeks until I'm back on the pitch," said the former Everton player.
"I'll hopefully train within the next 10 days, that's my aim. If I do that, then it's been a really good rehab - four weeks is very good.
"If it takes a week more, then it will be a week more just to be on the safe side, but we'll see - hopefully two more weeks is all I will need.
"It's a recurring injury, still my hamstring on the same leg. It's probably a different muscle - different areas of the hamstring.
"But I'm running well now and getting up to a good speed, nearly full speed. I haven't done much change of direction though, which is the next step and then ball work before I join the team.
"I've just got to be positive, it's just a minor setback and it's a long career. I'm still young and I just have to stay positive."