Welcome and congrats on your smart decision to improve your health, young lady !
1/ NO salt water flushes , no teas, no enemas recommended during Water Fast ...I usually have a tea the day before I start. Remember - water only , prefferebly destilled
2/ no problem flying 12 hrs either
Friendly recommendation - check some reading materials for WF, go over all recommended messages on the top of this page ( R/RR/RRR etc) - wealth of links and helpfull info in them