Lower abdomen feels weird?

<a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> says I’m in my fertile week (around 3 days in). I started taking prenatals around a week ago and about a day or two ago every time I wake up and need to pee, my lower abdomen feels hard and inflated. I’ve also started to feel super bloated but i was guessing it’s just the prenatals. Anyone have any clue as to what is going on with my body? Is this normal? Abdomen has never felt hard like this before.