You kind of left out some important information, such as the dose and the frequency of dose.

Pregabalin has a half-life of about six hours, so it ought to be taken four times a day, but that's not realistic. You may be slumping based on the period between doses. Also, although total uptake is not influenced by food, the peak blood concentration is. Your blood concentration will be smoothed out more if you always take it with food. So, twice a day with a meal might be nearly as effective as three times a day, with no consideration for meals.

As to the specific side effects.....I'm using this drug right now, and it is a weird one. Very tough to pin down, exactly what it does. Some days, I have such a problem speaking, that I have to consciously work my mouth, for example.

Depression is not an acknowledged side effect, but, it certainly could be contributed to by this drug. It could make depression more likely, I would think.

I also find that there can be significant morning-after type effects, despite difficulty in sleeping on it at all. I attribute that to the short half-life....withdrawal effect, occurring overnight. So, I take it as soon as I get up, with coffee. And I try to spread it out through the day as best I can.

Lar