Put it this way, having worked in the NHS all my life I know how many cock ups there can be! (Pardon the pun!)
In terms of finding out if you have been referred, call the GP and speak to the secretary - they should be able to tell you if you have or not.
If you have, contact the hospital outpatient department and make sure that they have the referral/find out when your appointment will be. Fertility is not exempt from the 18 week target, therefore you should really have a first appointment within (I'd say) 12 weeks tops. This is because they have to definitively treat you within 18 weeks of receiving the referral or, if treatment isn't required at this point, there needs to be valid reason for this.
If the hospital has received the referral and they say that you will be waiting for more than 14/16 weeks, contact the patient advice and liaison service at the hospital - they should be able to make sure you are seen within the required timeframe.
If your GP hasn't referred, you need to find out why not. It may be that they are waiting for another d21 prog which isn't in itself unreasonable. However NICE (2013) guidelines say that if a couple have not conceived after 12 months of trying for a pregnancy they are entitled to be referred to a specialist. However, be warned that if the specialist finds that there is no cause for a conception delay, there is usually a minimum period of trying to conceive for 2 years (sometimes 3) before you become entitled to some forms of complex NHS funded treatment (IVF and suchlike)