My pattern says to Make Bobble 2 (MB2) by [K1, p1 tbl] 3 times in next st. Does this mean to K1 tbl then p1 tbl in the same (next) stitch and then do it two more times in that same stitch?
Yep. Bobbles are rapid increases (like this, which is six stitches where you had one) followed, in a row or so later, by a rapid decrease (so you end up with one again instead of six). The extra stitches have no room to go, so they puff out in the bobble.