Help please - Automatic numbering of objects in photoshop

Hello Photoshop community, 

I am hoping someone might know how to achieve some 'automatic numbering' in photoshop (not to do with titles).

The problem: I took dozens of images of a place and I want to mark where they were taken and from what direction on a map with an arrow and number (see the image below for a rough idea of what I want to achieve).

Now, I can do this the difficult way by creating a new layer, inserting an arrow and then typing the number. However, this takes a long time to do for 50+ images and it really doesn't allow for me to make mistakes or change the order of my photos. For instance, if I decide I don't want Image 5 and I remove its indicating arrow and number, the entire labelling system is messed up. It just becomes 1,2,3,4,6,7... and so on.

I would like to know if there is a way to automate my numbers. That way, I could remove a number and arrow and the labelling system would rectify itself.

I hope that makes sense. Please let me know if you have any ideas! Also happy to consider other programs.