It’s normal due to the stretching of skin, DONT scratch it else when it turns into stretch marks you’re gonna regret. Apply stretch mark creams or if you got the budget, check out soskin (the mask for belly).
I’m facing this too! And it gets terrible in the middle of the night, waking me up from my sleep almost every 2-3 hourly. I’m currently spamming stretch mark cream, bio oil & suubalm to ease it.
Can try getting a small tube of suubalm (75ml)! It works well due to the cooling effect.