yes I would say she is... You will find that she will call/cry out while on heat... but the problem you have with female cats is that if they dont mate she will come on heat again very soon after and continue to do so... drove us nuts with our cat had to get her desexed in the end as we couldnt cope with it at all... took her in 3 days after heat had finished but the next one had already started again so cost us more...