Hi J.!
I'm 5 mon's pregnant and just got back from a trip to Bahamas so I understand your tanning issue and have a great suggestion, but can't help with the motion sickness.
I used Oil of Olay lotion "touch of sun" lotion. It worked wonders! I had so many people ask me about my tan. I was actually tanner before going than coming back! It has a slight odor to it, but not very noticeable to anyone but yourself. I asked several people if I smelled like tanning lotion and nobody said I did. I think I'm just very sensitive to smells. I didn't turn any shades of orange either which I know you can get from some lotions.
Good luck and enjoy your trip!