Why is it I go on winning streaks and feel like I'm actually understanding chess one day but the next day I'm completely lost and hit a mean losing streak?

Is this normal? It's like I have all my fundamentals down and clear board vision then suddenly it feels like I'm playing for the first time. Is this part of getting better or am I missing something? Might be a dumb question. I've only very recently started playing and my elo is anywhere from 480-610 (10 min Daily games)