Looks like I had green coolant in there but my local auto store only had:
Prestone® MAX European Vehicles (Blue) Antifreeze + Coolant
Am I screwed? Should I drain it ASAP?
Edit: the large tank was basically empty so I doubt any mixed yet but there was still some in the smaller tank
No worries Green and blue are relatively compatible. You’d be in trouble if you had put any other color in besides green/blue. You can drive to a shop to get it drained and swapped with no issues.