Im pretty sure that no Immigration office charges overstay fine in this specific case. But the passport is stamped 1 day overstay, that is always better to avoid, that's why the best advice is to extend the visa today.
In Penang you will have no problem to get 3 tourist visa in a row.
Don't forget that, before 60 day stamp is expiring, you can get a 30 day extension at Samui Immigration (monday-friday 8.30-12.00; 13.00-16.30) paying 1,900 baht.