I was wondering if it was okay that i took 5/10 mg of valium because of my morning flight tomorrow, a couple of hours before i start my 400 mg/7 days moxifloxicin cure?

It should be: I don‘t think there is an interaction between these two drugs.

Maybe (not) . . .: Best person to answer your question is doc who prescribed Valium & Moxifloxacin to you or pharmacist who dispensed them to you. While I didn't find any interactions btwn these 2 drugs (http://www.drugs.com/interactions-check.php?drug_list=1659-0,862-441), Valium is a mind/mood altering drug w/long half-life which means it could still be in your system long after your flight. So please ask YOUR doc