Is it a small tortoiseshell caterpillar?

Is it a small tortoiseshell caterpillar?

Observation - Is it a small tortoiseshell caterpillar? - UK and Ireland. Description: Moving very fast across pathway. I think it's a small tortoiseshell caterpillar but shouldn't there be more yellow on the dorsum?

Moving very fast across pathway. I think it's a small tortoiseshell caterpillar but shouldn't there be more yellow on the dorsum?