Everyone said it was new-baby tired. It wasn't.

After my second was born, I was exhausted in a way that didn't match the situation. She was a good sleeper. My first hadn't wiped me out like this. But everyone I spoke to had the same answer - you've got a toddler and a baby, of course you're shattered. So I believed them, because it made sense.

Except it kept getting worse. The weight from the pregnancy wouldn't shift no matter what I did. I was cold all the time. My mood dropped into somewhere flat and grey, and my hair started coming out in the shower in a way that frightened me. I assumed it was postnatal depression, and I felt guilty for not being able to keep up.

It was my health visitor, in the end, who gently said this didn't quite sound like 'just tired' and suggested I ask for a blood test. My GP ran it, and my thyroid was underactive. It turned out my thyroid had flared after the birth - postpartum thyroiditis - and instead of settling back down, it had stayed low.

The relief of having a reason was huge. I hadn't been failing at motherhood. My body was genuinely running on empty, and there was a name for it and a treatment for it.

Levothyroxine took time. The first few months were slow, and I had to be patient while they nudged the dose up and retested. But the version of me that could get down on the floor and play, that could think a sentence through to the end, came back.

If you've just had a baby and something feels more wrong than tired - the cold, the mood, the hair, the weight that won't move - please ask for a thyroid test. It's a simple one, and it's so often missed because everything gets blamed on the baby. You deserve to be checked properly.