I'm bottling my first mead. It is a blueberry mead where all the sugar was added in primary.

It was made 12/1/23, moved to secondary 2/1/24 and racked a third time 3/22/24 with a Gravity of 0.996 This racking included a campden tablet and Potassium Sorbate.

Yesterday, a week later I decided to bottle. Moving the carboy from my garage to my kitchen, i noticed 2 bubbles come out of the airlock. Worried, I took a new reading and the gravity was still 0.996 so I assume fermentation is completely done. I went ahead and filled up a couple 16oz swing top bottles.

I woke up this morning and opened 2 of the swing top bottles and there was definitely pressure inside of the bottles. Is this normal or am I setting myself up for bottle grenades?