CK, did she give you a little room thermometer with them? Gro put a thermometer in with them, complete with a clothing guide, so you can see based on what temp your room where baby sleeps is, combined with the tog you are using, what sort of clothes to dress bubs with.

If you don't have one, pm me and I'll send you one of mine - I've got about a billion

Fwiw I only ever had a 2.5 tog in 0-6mth size. And I had a feb bub and a July bub.