Gavin,
False awakenings can be incredibly annoying, but seeing as you were aware enough to continuously catch them, the next time it happens, just remind yourself that you'll wake up eventually. There isn't an infinite amount of REM available for dreaming. The fact that you were becoming worried about possibly being in a coma definitely wouldn't have helped; your dream would've catered to this mindset and therefore created more FAs. But, false awakenings aren't necessarily bad - although they can be a pain in the butt sometimes, they're often the most stable way to start a dream!

As for becoming bored, try eating stuff. There's the trees, dirt on the ground, strawberries that you can summon just by turning around and expecting a store to be behind you... So, just relax and have fun (whatever "fun" might mean to you, be it flying, sex, just observing the dreamworld, etc).