The Robins could only managed a solitary Liam Atkin try, converted by Ryan Shaw, as they slumped to a heavy defeat.
Sheens said: “A 6-1 penalty count in the first half, followed by 18-9 overall and a sin-bin off it as well didn’t help us,” said Sheens.
“Then with what ball we were getting, not finding touch and losing it on first and second tackles and not playing the ball square. They are the things you can’t do when you do get an opportunity.
“We have not won a penalty count this year, to my knowledge, and I’m pretty sure I’m right there.
“From the outside looking in, it may look like our discipline is really bad.
“But when I phone the league, they’ll say that shouldn’t have been a penalty and that shouldn’t, maybe there will be some of those today. But yeah in that area, I was disappointed. We did some silly things.
“If you do a high slappy shot, that doesn’t do any damage, but is a penalty. Most of their penalties were that golden penalty, where you piggyback them up the field. That is what concerns me and that turns you brain dead because you don’t have enough ball.”
Sheens was obviously disappointed with not picking up any points over Easter, but he cannot complain about their effort and he believes once they get some bodies back the results will start to come.
“Obviously for 30 minutes in the first half we competed well and then our right edge copped a bit of a hammering with some very deft kicking in behind. Quite a few of their tries came from that. I think six tries came from that same kind of play and we failed to rectify it. The guys tried, but we are just not putting it together as a group at the minute.”
Leaders St Helens made it back-to-back wins over Easter with a comprehensive 28-6 win at Widnes Vikings yesterday.
Mark Percival and Tommy Makinson scored two tries apiece with Ryan Morgan and Ben Barba also dotting down as Saints kept up their four-point advantage over arch-rivals Wigan.
Wigan Warriors: S Tomkins, Davies, Sarginson, Gildart, L Marshall, Williams, Woods, Navarrete, Leuluai, Flower, Isa, Farrell, Bateman. Substitutes: J Tomkins, Sutton, Ganson, Hamlin.
Hull KR: Quinlan, Shaw, Minns, Salter, Carney, Atkin, Marsh, Jewitt, Lee, Masoe, Blair, Greenwood, Clarkson. Substitutes: Scruton, Donaldson, Johnson, Dagger.
Referee: Ben Thaler (RFL)