Autumn Carrots have not germinated

[Hollie the Wollie]

I planted some autumn carrots (Autumn King) last month where the spring onions / regular onions had been.

With the exception of one, right in the corner, none have germinated. I'm upset about it as I like carrots

Are there any reasons why this may have happened? I followed the instructions on the seed packet. I also caught my dog this morning peeing on the veg patch (now almost empty) as she didn't want to go on the wet grass!!! She may have been doing it for a while.... would this have killed them?!