My find my phone keeps showing a greyed triangle, meaning it been used in the last 24hrs, my question is, is this an automatic thing or is someone tracking me ?

Hello and welcome to Apple Support Communities Thegroovyfox,

I see that you have a question regarding Location Services. I'd be happy to help answer your question.

The gray arrow that you're seeing indications that an app has used your location in the last 24 hours. If you go to Settings > Privacy > Location Services, and scroll to the very bottom of that page, it gives a description of the different arrows that you may see.

Hope this helps.

Have a great day!