I'm greatly helped in following my AFIB by an up to date Apple Watch and an iPhone which (with the watch) can provide a read-out of sleep and round the clock heartbeat feedback through both a Cardiogram and Sleepwatch app.

Re triggers, I too have noted late eating (especially if more than I ought to) is a major trigger.
Recently I've also become aware that alcohol is a main trigger even in small quantities, and late exercising increases the likelihood of nighttime AFIB with tachycadia too.