Wearing rings when you're not engaged or married

I inherited my grandmothers ring recently and rather awkwardly it only fits my wedding finger and even that it is a tad tight. I tried the ring on all of my other fingers but it is either too small or too large for them so I have been wearing it on a necklace chain for the time being. 

It got me thinking though about wearing rings on other fingers before being married or engaged. It is something that I have never done before as generally the few times I have worn a costume jewellery ring I have ended up taking if off after a few hours because it was irritating me and getting in my way. Recently though I have been thinking about experimenting with costume rings again and I am really tempted by the cute little stacking set from Accessorize shown below!

What do you all think? How many of you wear costume rings on a regular basis? Am I over-thinking this as usual?