She's in a hammock, so not flat anyway. Will try the towel think. She's got quite a cough. Would you go to the doctors? I know it's just a cold but not sure if you need to be worried in babies this young.
Have you got a bulb nasal aspirator see here? Once you put in the saline drops you can then suck out some of the mucus that is affecting her breathing. Although I found just sucking it out myself more effective, but you have to suck gently in short bursts otherwise it can harm the baby's lungs. Once she reaches 12 weeks if she gets another cold/chesty thing this winter try the Karvol vapouriser, my DD (17 months) just recovered from a three week long chesty cold and having this plugged in at night did help as it produces vapour all night so that you don't have to keep rubbing vapour rub on constantly. Also sucking motion of breast or bottle feeding helps clear nasal passages, I find gently massaging from bridge of nose out across cheek bone when feeding can help clear sinuses further. When feeding try to elevate head slightly more than normal to encourage sinuses to drain.
Don't want to worry you but when ds2 was 20 days old he had a cough and cold I went to the doctors 3 times 1st time was sent away with nose drops next day we were given antibiotics 3rd day we wre sent to hospital it turned out that ds2 had broncholitis and spent over a week in hospital on oxygen he was really poorly
In the answer to the calpol question yes I would give a small dose x