Are you wearing your baby with their legs inside the sling? If so, yes, the fabric may fold over a bit along your back or at your side because the lower rail of the sling (the hem) winds up higher on your torso then it does on your back. Does that make sense? Anyway, it shouldn't be a full twist, just a few inches folded over. And if you are careful, you can have that fold be more so at your side so that the fabric will still spread out across your back.Â
Â
That said, that in and of itself shouldn't really make the sling too uncomfortable. I would recommend making sure that you are wearing the baby high and tight against your body. Most people make the mistake of having the sling be too loose, but when it's loose it can cause back strain. Ideally when the baby is in the sling the lowest part of the sling (baby's bum, usually) should be around your natural waistline/above your belly button and you should be able to kiss the top of their head easily just by bending at your neck.
Â
If you could post a pic of yourself wearing the sling it might help us troubleshoot better. If not, I'd recommend watching a few online video tutorials for ring slings. I know Maya Wrap has instructional videos but sometimes people explain things differently or change something up a little bit and it just "clicks" better then another explanation.Â
Â
And yes, there are lots of types of carriers I'd recommend. It really depends on what you are looking for. The Ergo is a nice structured carrier but it's not my first choice for a baby at your's age/weight. A Beco Gemini might be a good choice, so would something like a mei tai (BabyHawk, FreeHand, Mei Tai Baby). Woven wraps are nice as well, though they have a little more of a learning curve.
Â
Hope that helps. :)