Strange sensitivity, potential root canal?

[GingerSoftwareDev]

So, I've been having some cold sensitivity (liquids and breathing in) in a composite filled (2 years ago) LR6/#30 tooth for the past week or so and been to my dentist to get it checked out, there appeared to be no signs of a crack in the tooth, no issues with placing pressure on the tooth and what's strange is if I cover the gap between my pre-molar and this tooth and drink anything cold then the pain is not there.

I have attached my X-rays for anyone to take a look at to confirm the suspicion of no infection or issues with the pre-existing filling.

I am focusing on using Sensodyne Deep Repair toothpaste and have recently started flossing (after never ever having flossed in my life), my personal suspicion was that the gum between my 2 teeth could be inflamed and causing some sensitivity, though I am aware that if the sensitivity worsens or the pain hangs around for longer then a root canal will likely be needed.

I'd really value any input, thanks in advance.

 

[Gordon]

No sign of infection (wouldn't fit your symptoms anyway). The filling looks fine on the x-rays but that's not definitive.

There's a little bit of bone loss between first and second molars, this will expose a bit of root surface which I suspect is causing your problem.

Keep flossing. Last thing at night massage some of your Sensodyne into the sensitive areas then leave it be, don't rinse, don't spit, go straight to bed without supper
If that doesn't work, ask your dentist about using a stronger desensitising agent.