Breathing pattern. Else test do i need?

Hello my ige level has come out to be 275 and dt. Said that it means i have allergy. But for last 2 months i have experienced a change in my breathing pattern while standing up.. my stomach goes in sometimes when i want to deep breath as if it contracts to my rib cage.. i asked about this to the dr , he said that it may be because of allergy but i am not sure. It looked like he was also not sure.. This does not happens when i am sitting or lying down. May be i notice more.. but i experience this. Got a PFT done and the reports are ok. What can it be then?? What else test do i need?? Any ultrasound or xray of stomach.. Please explain.. I am developing anxiety because of this. I have lost 4 kgs wt in last 2 months because i cant sleep properly or is it a sign of something else.. Please help me