Am I dressing my baby in enough overnight?

I'm re reading the tog guide on my love to dream swaddle packaging and realising I might have misread it, I just put him in a long sleeve footie overnight and his 2.5 tog sleep sack and that's it... he's absolutely fine, sleeps for about 8 hours solid and wakes up happy and smiling so I'm assuming its ok? Its usually about 18/19°c in our room and he's 6 months (4 months corrected). Am I overthinking it?