I recently had labyrinthitis (inner ear inflammation) which caused horrendous dizziness/vertigo - it was like everything was spinning, and that spinning sensation in turn caused awful nausea. It sounds like your dizziness isn't as bad as that, so probably not labyrinthitis, but something to consider looking into if the dizziness sticks around or gets worse. For me it lasted about 2.5 months total, gradually getting a little bit better each day until it finally went away. Walking around helped improve the symptoms - it's like, the inner ear gets inflamed and then it can't tell the brain where you are in space, so if you walk around then that helps the brain re-acquaint itself with where your body and head are in space and the dizziness then gets a little better the more you walk. And for me the symptoms were worst first thing in the morning & last thing at night, so similar to what you said. Like I said, it probably/hopefully isn't that, but it might be something to ask your doctor about if things don't improve.
