Hi Sir or Madam
I hope my answer brings you confidence that you can help yourself and a direction in which to begin.
Try booking a session or two with an EMDR therapist - EMDR is Eye Movement Desensitisation and Re-Processing and it works like this; when we are asleep at night, we drop into REM (Rapid Eye Movement) sleep, where our eyes move very quickly from side to side, processing away any stress or tensions that have experienced throughout the day. When we have an experience that is highly emotional (winning a race, accepting a medal etc.) we can almost touch the memory "as if it was yesterday" with the sounds, textures, emotions etc. linked to the memory very vivid in our mind. The memory is stored away from other memories and is not processed away during REM sleep. If the memories are good, that's great, we can recall them to boost our self confidence, etc. However, if the memories are less good, they can also be recalled (often subconsciously) and bring with them a fear or other negative emotion. The memories can hold beliefs about ourselves in our subconscious mind, which stop us from doing things again; for example, I worked with a lady who had been in a car accident when she was 17 and she was now 42 - during the accident her mum was driving, and she said 'brace yourself, we're going to crash'. Unbeknown to the lady, at that very moment the memory stuck in her mind with the belief 'I'm going to die'. Years later, when this lady wanted to drive her car alone, she was unable to do so and didn't know why - the subconscious belief 'I'm going to die' was being triggered each time she got in the car to drive and she was unable to do it. After one session of EMDR, she was able to have two more driving sessions with others and then was able to drive alone. The EMDR allows the client to recognise their own negative beliefs in relation to the incident and to let them go, using a bilateral stimulation (either from eye movements, tapping or gentle electric current). You will not be expected to know the answers to these things before the session, but will be led through every step at your own pace. The reason that the subconscious mind does this to us is because it's sole responsibility is to keep us safe from harm - if it's attention is brought to a 'dangerous' situation (such as an accident or injury), it becomes active when it believes the situation may be repeated (hence people fear flying, driving, dogs, etc etc). There are no guarantees with therapy, but you may be surprised at how relatively quick and effective this therapy can be, and how soon you will be back to your athletics. You will find a local therapist to your area on the internet.
I do hope this information is useful to you and that you will push the 'accept' button so that I will be paid for my time. (Sorry, my answer will appear twice, I am trying to get this fixed).