Kitten vaccination

Hello,

My kitten received her mandatory Typhus/Coryza vaccine at 8 weeks old, followed by a booster at 12 weeks old (in France).

At 24 weeks old, I brought her to the vet for neutering, and the vet (in Belgium) told me that she should have received a third injection at 16 weeks. So, she gave her another injection at 24 weeks and told me to come back for a second injection at 28 weeks.

Is this really necessary? It seems like a lot of injections for a kitten, and yet I keep reading that the standard protocol consists of onlt two injections...

Thank you for your help