Like caffeine, many people are aware that daytime napping can be problematic for sleep. If you have had a rough night of sleep, you may find a strong desire to nap the following day. Most people will report that this urge occurs most commonly during mid-afternoon or early evening.
One issue is that while you may feel tired or sleepy, you may still have trouble actually falling asleep for a nap (particularly for those folks with insomnia). The research tells us that individuals with insomnia tend to be more physiologically aroused which reduces their ability to settle in for a nap. This can increase feelings of frustration and anxiety about sleep.
The verdict on napping is that it is not necessarily bad. Many of my clients report that naps increase their afternoon or evening productivity for example. It becomes an issue if/when individuals nap for long, sustained periods of time (typically longer than 20 minutes) and/or if they nap later into the day or evening (i.e., closer to bedtime).
*A good rule of thumb would be limit your nap time to 15-20 minutes (i.e., set a timer on your phone - I know you have one), and be sure to have your shortened snooze before 3:00 p.m. in the afternoon.