2 weeks is way too short for primary man!
a cyser is a style of mead. general rule on mead is 1 month in primary, then it goes to secondary to age for another few months.
long story short, you're rushing things by about 6-12 weeks...bottled early, and got a volcano.
if this had been capped with a normal beer cap, the bottle would have exploded. NOT COOL.
gotta be more patient with this stuff.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10