Went to see new chiropractor. He's got more knowledge about the sort of exercises I do. I explained it all to him, and he then checked things out.
It looks like my leg length difference is about 6mm, which is actual leg difference, as my pelvis is symetrical (im one of the 1 in 100,000+ who has this). This is causing a fair amount more stress on my right hand side (knee, hips, back), and then caused the piriformis to tighten, which is causing tightness and radiating the soreness around other area (like groin), its apparently tight, and is tender. This is catching / putting pressure on the sciatica nerve, which is what caused the pains before, and why I have experienced nerve pulses and contractions down the back of my leg (this is the weirdest feeling ever! Also when he was pinching the sciatica nerve in my back).
So im booked up again for next Monday, and he said we'll try and get things back to normal before holiday (so I dont have any problems, and can enjoy it). A few more back manipulations (will probably be regular), and look into a specialised insert for my slightly shorter leg. Once initial bit has gone, will get a few sports massages for the areas.
Although, as mentioned, in some way, its better I picked up on things now (or in more detail), as the problems would have been greater in years to come.
Ice packs tonight and maybe tomorrow, plus neurofen. Giving any exercise rest for a few days. Also keep up core work, mobility exercises, stretching and foam roller. Feel happier now that I know what this is, and that it should be sorted eventually. Still going to cause some discomfort though.
Many thanks to the people who have posted, greatly appreciated.