I have an IPA that’s been fermenting for 12 days. I still see very small bubbles or fizzes popping up sometimes. Is it possible that its not done? Sadly I didn’t take an OG reading.
Can fermentation be done while you still see these things?
Yes. After fermentation there is a lot of CO2 dissolved in the beer and it will slowly leak out. Also, if the room is slowly warming the air in the headspace will expand and that will also cause bubbling. At 12 days, it really should be done. But you only need FG readings to see if it is done (take 2 a few days apart and see if it changes). If they are the same and it tastes good, bottle it up.
Never rely on appearance to find the end of the fermentation - specific gravity is the only way to know for sure.
Yeah, but I didn’t get OG 
That doesn’t matter. Two gravity readings that are the same over a few days and you know it’s done.
additionally, with extract batches, assuming you were reasonably close on volumes you be reasonably close to what the kit and or computer program tells you the OG should have been.