Uk ladies I need some advice about doctors.

•Jade•
So I just need a little insight as to what I do next. If AF doesn't show her ugly face within the next few days me an OH have decides to go and seek medical advice. We have been trying officially for 2months (SMEP) but have never prevented on or around my OV days before this. 
But my question is do I just go to my doctor and say I would like some fertility tests or do I have to go to the hospital for something like that?
I may sound really dense for asking this sort of question but I have never been to my doctor for years, simply because it's much more convenient to go to the walk in center and see a nurse. It's so much quicker. 
​Or could I go to the sexual health an maturity ladies and ask them? I am really at a bloody loss as to what the next step is!  
​Thanks in advance Girls.