You can turn them from 9 kgs, but generally you don't have to until 12 kgs, for most seats anyway. The recommendation now is to keep them rear facing until at least 12 months (or so I've been told). My DS is 16 months and still rear facing! (at 10.5kgs).
I wouldn't be happy either hun, sounds like you'd be better turning him around again.
I agree with the others. Probably best to turn it back to rearward facing again. As to being over height and weight recommendations, I suggest you call the helpline for the manufacturer.
I would agree to turn it back, we too turned ours early as Charlie was very long etc & soon realised his head would fall forward & it wasn't that comfortable for him...so we turned it back for a few more months. We now recline the car seat & use a neck pillow thing IYKWIM.
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