Pink eye, poor weight gain, and possible breathing problems

So, Rory was weighed last week. She's almost 20 months old, and weighed 18lbs 11oz. She has lost and gained in between, but that is only a 1 lb 4 oz gain total in 8 months. Now that her reflux has been good, and she is eating, we are wondering if there is something else going on. She has been holding her breath for many months now. When I mentioned this to her doctor, she said she recalled us mentioning it before when she was younger. Well, it seems to be getting worse. She has had a cough and cold going on 6 weeks, which we attribute to daycare. Unfortunately, the breath holding has too. The doctor seems to think it is just "Rory", that it is nothing to worry about, since she has always done it to some extent. We are wondering if she is actually having trouble breathing, and if it could cause her to burn up all her calories. The video makes it sound like she is just stuffy, but I assure you that this has been ongoing well before she got her "cold that never quits". It is all day, every day. To top it all off, she has had pink eye in both her eyes since Thursday afternoon when I picked her up from daycare. Four days of drops have done nothing. We are off to the walk-in clinic tomorrow, since the dr's office is closed for Remembrance Day. To hear the breathing video, turn up your volume.