Between May 31 and June 1 of this year APU dropped as much as 1.14 to 37.41. That was less than 2 months ago. The large, occasional drop, like the one today mean nothing more than buying opportunities. They happen, maybe randomly or maybe they're caused intentionally, but either way, they're normal. I'm buying, now, because this is a great buying opportunity.
I agree. The daily average volume is pretty light and the bid/ask spread is often wide. I usually manage to miss the dips and I see it's up in the after market, but I'm probably going to buy in the morning if it doesn't run up too much.
You really need to get to know the "personality" of a stock. What might be a disturbing move in one stock. Is just a normal event/opportunity in another.