I need a pick-me-up ASAP!

I've been feeling very drained as of late.
It's like an invisible vampire had sucked all the energy out of me.
After a long day at work, I just wanna lie down & do nothing.
I don't even go to the gym as much as I used to anymore.
I can't even make myself stand up for long let alone run a few laps on the treadmill.
I'm not sure whether it's old age (is 26 going to 27 old already?) or I'm PMSing.
I've been like this for almost 3 weeks & I should have had my period 2 weeks ago but no sign of the 'Japanese flag' so far.
I'm not pregnant, just late ok?
:D
Maybe I'm just stressed out about something (or someone) & it's taking a toll on my body.
Tell me what I should do to feel better & get my energy back.
Coz at the moment I just feel like a frigging sloth.
:(

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