Hi John,
Welcome to the Forum
Have you been diagnosed with CTS ? The reason I ask is that many 'repetitive strain injuries (RSI's) are often 'lumped' as carpal tunnel syndrome. Carpal Tunnel is often suffered by typists, manual workers and musicians (hence my awareness). Make sure you rule out arthritis.
As Kev says get to the Doc, however a referral may take some time (whatever NHS target times are) and it may be some time before you actually see a hand surgeon pending scans, x rays etc. Going private will speed things up. Surgery can prove successful in bad cases but there are other options.
Though I haven't suffered from it I do know that CTS is caused primarily by inflammation of the tendons that run through the carpal tunnel in the wrist - basically the tendons swell up and don't fit through the space there that runs to the hand and fingers causing considerable pain to surrounding nerves. Classic symptoms are not being able to sleep it is so bad.
Ice dips can be really good (I use this as a preventitive). Fill a basin with cold water and put as much ice and frozen bottles in as you can. Dip BOTH arms in flat and up to bicep if you can for 10 seconds ( you will struggle to do more if you have the temp right). Swearing a lot whilst doing it helps ! Repeat every 15 mins for an hour or so. Your arms go numb but warm up as blood flow returns and this action naturally reduces inflammation. Using anti-inflamm drugs whilst doing this treatment can also be effective apparently.
One last thing, most RSI's are caused by ADL - activities of daily living ! It is not your fishing causing the problem ! Try to find activities that cause or aggrevate the symptoms and stop or limit them if you can (hard if it is your job). Most cases of CTS settle down on their own without surgery but in extreme cases this may be the best option.
Good luck with it all,
Lindsay