The main issue must be .. have any of the tyre cords been damaged? A puncture with something like a nail or a screw will do more damage than a thorn. Nothing to lose by getting the advice of a decent tyre specialist once the tyre is off and can be inspected. Different if the actual sidewall is damaged.....the tyre needs to be replaced.
There is a big difference in going to a
Quick-Fit take your money centre and a Specialist you trust to show you the condition of the tyre, as suggested here by Jay.
When working on commission its easy to frighten someone by suggesting Safety is paramount, if you are lucky enough to of been involved in the Motor trade and worked around tyres all day, you soon learn what is worthy and unworthy.
A good tyre fitter will remove the tyre, spread it and show you the fault. plus its not only about safety at speed, HGV tyres carry very heavy weights over Hundreds of Thousands of miles pa, those tyres get re-cut and Vulcranize repaired daily and that is legal even when carrying Dangerous Goods.
Tyres are a cut throwt business, repairing them doesn't make the Company the profit it makes by replacing them, hence you will inevetably 99% of the time be informed
IT NEEDS A NEW ONE SIR/MADAM 
