Just putting it here in case anyone has to do it (I hope no one ever needs it): it is NOT painful at all.
I was told “it’s like a grenade explodes in your spine” by a (stupid) friend, it caused me to refuse to do it for the first time, which if I went through with it, things would’ve been very different for me, I would’ve been diagnosed days faster.
Again, it’s NOT painful at all, they use Lidocaine, you’ll feel way less than when they draw blood from your arm.
If it’s needed, don’t hesitate.