Just starting on BC

So I just started taking birth control yesterday around noon, I think the one I have is called Junel Fe or something. I am thin so I was prescribed an easy dosage so that my body wouldn't be overwhelmed. Last night, I felt very nauseous and it felt like my mood was constantly back and forth.

My questions are: Is this normal on the very first day? Do the side effects eventually go away?

I'm sorry if I seem really dumb right now, I'm just kinda nervous about just starting!