I think the fact your Dr said 'at least you are ovulating' in regard to your luteal legnth just shows how mis-informed she is!
Yes, it is a good thing you are ovulating, but if you do have a short luteal phase then even if an egg gets fertilized it won't have time to embed properly as your period starts that little bit too early.
I generally find GPs a complete waste of time when it comes to fertility, they really don't have a clue. I found the book 'Taking Charge of Your Fertility' by Toni Wheschler an absolute godsend and it helped me to achieve pregnancy within a couple of cycles. Its also got a tear out section at the back specifically to give to your Dr (as the book recognises that most Dr's are rubbish when it comes to fertility).
Personally I would go and see another GP who knows what they are talking about!!!!