breathing trouble/dilaudid

a couple months ago i took some expired dilaudid. i had it stored from a previous injury and decided to try one or two. i don't usually do this sort of thing. i wish i didn't that time. a few days later i began having trouble breathing. or rather i was uncomfortably aware of my breath. it felt like it might get stuck, or i might forget to breather. at certain points it felt like i'd forgotten how or my body just wasn't going to do it anymore.

i went to the hospital and they hooked me to something they give asthma patients which didn't help. everyone said they thought it was an anxiety disorder. i can't remember if they did extensive procedures on my lungs or not but everyone seemed to think it wasn't that big a deal. i shortly after had a surgery for stones in my common bile duct. they gave me dilaudid and at one point it felt like i was dying, i couldn't catch my breath. i haven't been on it since.

i read that dilaudid can cause breathing problems but i can't find any information as to whether that can continue after you stop taking it. did i just develop an anxiety disorder coincidentally around the same time as taking it? or did it introduce me to the possibility of being unable to breath and thus giving me anxiety. i still occasionally have difficulty breathing.