@GrantGam Thank you for your reply. It has all been fairly settled and nothing dramatic has happened as I expected from too much basal rather than too much quick acting. Luckily I'm off work this week so I can be as lazy as I like today!
Overnight was fine. I did go to bed higher than I usually aim for at 8 and woke up at 6 so your advice wold have been spot on.
I'll try and make sure not to have this happen again, silly how a tweak in normal routine can muck things up.