Time heals! My first batch of beer was the same, at 10 days I had HUGE carbonation, the head in the glass was taller than the beer! But then the head would dissipate and it was almost flat/hard tasting. After 4-5 weeks it was reaching prime and the carbonation was perfect with no off tastes. Let them rest a while longer. Be sure to put the beer in the refrigerator for at least 2 days before drinking so the CO2 can re-absorb into the beer.