I really do suggest you nip it in the bud,
now before your mind runs off with other fears and anxieties.
Quite recently, I went through an experience where I can say I felt the exact same way, and in hindsight I'm able to say a small aspect of it was self induced. I was
Hungry,
Angry and
Sleepy... lets say over a week of rarely any sleep after dwelling on stressful pieces of my life. (Yes I made an acronym for it in order to keep in check the reasons why my mind may get away from me.)
I can only suggest, from my experiences.. that you take care of your physical state first and foremost, as it correlates with your mental mind frame. And no, these feelings do not just 'pop' out of nowhere.. there is a point where you really need to look inside yourself and be honest about why your emotions are filled with paranoia or anxiety.
GOOD LUCK