He told BBC Radio Suffolk: "One of my biggest disappointments this year is not being able to offer a bit more to the manager and the lads.
"That's something that's been a little bit personal and something I've actually been a bit embarrassed about."
Irishman Kennedy tweaked his hamstring on his Town debut against Middlesbrough and then returned to action a month later only to suffer a similar injury after six more games.
He is now two matches into his latest come back and hopes his fitness woe has subsided, so he can help Ipswich climb up the Championship table.
When we brought in Kennedy I think there was a collective sigh from all of us!
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"Although I haven't let anybody down, that's what it feels like. Being on the sidelines and not being able to help the lads is very frustrating," he said.
"If you look at the other side of it it's not through any fault of my own, there's nothing you can do when you pick up a few knocks.
"I'm very grateful to the staff and the manager for the work they've done with me."
Midfielder Shane O'Connor made his return to the starting line-up in last week's defeat of Leicester City at Portman Road.
The 20-year-old Irishman, who made only his fourth start of the campaign on Saturday, has been overlooked by boss Roy Keane for the majority of the season and admits it has been a tough few months.
"I'm not going to lie it's been quite hard. I'm very lucky to be where I am as a footballer," he said.
"Although it was quite hard to take from a personal point of view I still look at it and think I'm very lucky.
"The manager is very fair in that way, if you keep your head down and work hard he always acknowledges it."
Source: BBC Sport
Source: BBC Sport