Usually when you hunt for them in a ten minute span you will find 2 cupids also if you hit it once you still get hearts. Once you get 10 don't save them just run to the holiday shop. It worked for me I got 5 valentine hats and 580 throwing hearts so far.
I should have around 300 valentine hearts right now but everytime I take a base it resets them and gives me 1-2 in their place. I think it also resets them when I go offline for a long time. This really sucks and even 2 weeks AFTER vday it still isnt fixed.
someone made an account under my name the same day era-go was released and it was banned shortly after... thats why I have a "z" before my name if you were wondering x.x