If you get lucky enough to end up in space, watch out for motion sickness. Your inner ear gets confused, muddling your brain and socking your stomach with "sick sick sick" signals. This could turn a space capsule or station into your own private barf bag. Don't pin your hopes on motion sickness drugs—they raise the bar for getting sick, but that's about it.
Weightlessness is a hazard. Without the tether of gravity, bones thin out and muscles deteriorate, and you could be barely hobbling when your mission ends if you aren't proactive. Bones take about three to six months to recover.
Space exploration isn't called high-risk for nothing. Shuttles may blow up. Parts may malfunction. Astronauts could slip their tethers. The landing could abort. Crew mates could come to blows, depending on the irritation factor.
But hey, no pain, no gain.