Foot Pains?

Hi all! Quick question about some recent pains I've been experiencing in my foot. I started properly running at the end of June during lockdown (as I'm sure many did!) and ran consistently for quite a few weeks (probably until mid-July). In hindsight I probably overdid it a bit because I then started getting some pains around my foot and ankle. I then rested for a number of weeks and have only recently (end of July-ish) started picking up the running again. I'm quite young (U18) and as my dad is a runner I've been using some of his running trainers. My feet are slightly larger than his and I recently got a blister on the underside of my foot after a recent 5k- could this be why I'm experiencing foot pains (other than the blister)? It's difficult to describe how it feels because it changes, but I suppose it's mainly that I feel as if I'm putting 'too much pressure' on it? Like every time I take a step it's putting stress on my foot although I know it shouldn't feel as uncomfortable as it does. It does come and go though and I can only judge it after I start running which can make for a quite unpleasant time (especially if going longer distances).

So I suppose what I'm asking is what could the possible cause of this be? Ill-fitting trainers? Doing too much & not giving myself time to rest? Or maybe it's form. I've been reading about making contact with the 'middle' of the foot (neither heel nor toes first) and have been trying to incorporate this although this doesn't feel any more comfortable. Thanks to anyone who has any idea!