Measuring big

The last couple appointments my doctor said I've been measuring about 4-5 weeks ahead, so she scheduled an ultrasound, and my son is also measuring big.

I'm only supposed to be 32 weeks, but we're measuring close to 37.

I never had a period after getting the mirena taken out in Sept, so my due date was based off my first ultrasound which they measured the baby at 6 weeks.

Anyone else going through this or have went through it? It's so nerve wracking!