Sometimes I feel sleepy in the afternoon. Is that a sign of narcolepsy? Thank you very much. :)

Possibly. GabitaM, while it is true that patients with narcolepsy can have sleepiness in the afternoon, there are a lot of other much more common reasons for this as well. Much more concerning for narcolepsy are "cataplexy" (episodes of weakness with emotion), waking dreams, sleep paralysis (waking up but being unable to move) and dreaming with short naps. Lack of sleep, insomnia and apnea are possible.
Possibly... Narcolepsy is a very specific sleep disorder, and is one of a list of possible reasons for daytime sleepiness. It is a diagnosis of exclusion, meaning you have to rule out all other possibilities such as sleep apnea, poor sleep hygene/habits (like watching TV while in bed), or plain sleep deprivation. A special study, an MSLT, is diagnostic. Make sure not to confuse narcolepsy with cataplexy...
Unlikely. Narcolepsy is "numbness and attack" four typical signs include 1 day time sleepiness, so severe that it equals 24-48 hours of staying awake without sleep. Even while in a car which is obviously dangerous. 2 REM sleep after 5-10 minutes, instead of 1 hour 3 sudden muscle weakness, triggered by laughing or anxiety or terror or crying. 4 inability to sleep Therefore, one sign does not mean NARCO.
No. Narcolepsy is suddenly falling asleep without warning. It is very natural to feel tired in the afternoon, as this is a time when your cortisol level tends to dip, which can cause sleepiness. If you have the time in your schedule, enjoy a short nap. It will refresh and revitalize you. Hope this helps!