My little girl has had a persistent cough for 7 weeks and has lost weight. She's always tired lies around most of the day. Complains with joint pain and is just generally unwell. They are treating her for asthma blue and brown inhaler and added montelukast on Thursday. I'm just convinced there's more going on then asthma. How can I get my gp to order blood tests to check there's nothing more going on. They have done chest X-rays which were clear