The thing that makes me think it's probably anxiety not bipolar related is that it happened a lot as a kid but overall I was happy, if it was bipolar I would assume I would have been far more unstable a lot of the time & I wasn't. So the fear doesn't seem to be related to any particular potential "mood episode" as a kid. I did get sad & have physical symptoms of illness like abdo pain, nausea & diarrhoea at the beginning of the school week too. Even though I was smart & liked school it still overcome me most Sunday nights. These days I'm obviously more aware of when I'm feeling anxious/paranoid & it does seem to be much worse during a mood swing now. In particular during dysphoric hypo mania. But it can happen anytime out of the blue & ill panic.

Benzos do a good job to help aswell. The only antipsychotic I've ever taken is seroquel & only at 25-50mg doses. That almost made me more fearful.