No, not too early to do a treatment - I personally recommend Vape of Oxalic Acid - 3 treatment 5 - 6 days apart - the reason for this is the sealed brood are not treated - the full brood cycle is 24 days for Drones you need to get the larvae when unsealed - that is why you need to understand the bee life cycles.
3 days egg, 6 - 7 days Larvae and 14 - 15 days as sealed.
Doing the vape over 15 -18 days covers the whole brood period for Drones and the whole hive is treated.
Wipe the correx/corflute board it can have a light smear of oil if you want.
Watch the Varroa drop over 3 weeks - wipe the board and see what the drop is 1 week after the last Vape.
That is how I do it.