I drink two sodas a day.
Do I have insomnia?
When you have trouble sleeping, yes. Nothing else to call it.
Since you arent using a sleep-aid every night, though, you are way ahead of things.
Cutting down/out caffeine is normally the first step, since the shit accumulates. But it sounds like you have that under control. If you reduced to one soda, though, you will be surprised what a difference that can make. The only problem is that it sounds like your issue is random within the week, so you need to know how to target that day/night.