Recurring pain in foot - exercise related

Hi there, I wondered if anyone has any suggestions of what might be up with my foot!

I'm a 28yr old male, and have been experiencing a recurring pain in my left foot, which feels bone related (though I'm not sure). It came on all of a sudden about 6 months ago, apparently out of nowhere, and left me unable to walk properly for approx 3 days, before it all of a sudden disappeared. It has reappeared fairly regularly over the months, maybe 8-10 times where I have noticed it enough to not be able to walk comfortably, though thankfully it's never quite been as bad as that first time. Its appearance usually seems to follow a bout of exercise, though not always. This week it came back fairly badly and the night before I had been doing leg press exercises in the gym, which I don't usually do.

The pain is located on the inside of my foot, approx halfway down from my ankle to my big toe. Looking at a diagram of the foot bones, I would say it's around the cuboid/medial cuneiform/intermediate cuneiform bones (or the joint(s) between them). It hurts only when I walk on it, and feels almost like something needs to "crack" to relieve the pain. When the pain is there, if I instead put weight through the outside or the inside of my foot while walking, it doesn't hurt - only hurts when I walk normally with my weight going through the normal force plane in my foot. Also, the foot feels stiff and the pain is at its worst when I start walking - i.e. if I have been sitting down for a while and then get up. The more I walk, the less it hurts, until it simply disappears after a while... but then comes back on next time I sit down and get up again. When it comes on, this all lasts for 1-3 days before it completely disappears again.

I play football (soccer) twice a week, swim once a week and do a bike session in the gym (45-60mins) once a week, and occasional weights sessions. The pain does seem to come on after the bike sessions more than anything else - so possibly something to do with the forces going through my foot as it pushes the pedal. Soccer doesn't seem to cause it. I only started exercising at this level at the start of this year, 2-3 months before the pain started, so I am pretty sure it's related to this. However at least once it has come on out of nowhere, apparently not after any specific bout of exercise.

I have changed both my work shoes and my trainers once in the last 6 months so I'm pretty confident it's nothing to do with that.

I have been wondering if its a stress fracture - not that I have experienced one of those before - but it feels sort of like what I would imagine a stress fracture to feel like... could be completely wrong though. I am reluctant to go to my GP at this stage before I try and learn a bit more about what might be wrong with it, though an x-ray could help I suppose.

Many thanks in advance for your help...