6.5 month old suddenly waking every 45 mins at night

[Lainey1981]

Hi,

Please anyone offer me advice or reassurance. My 6.5 month old ds has slept through the night 9-7 ish since 10 weeks old which has been great. But for the last 5 nights has been waking up every 45 mins or so. He whimpers but doesn't cry so it isn't for food I don't think. A coupld of the nights he has had a long awake period of at least an hour where he has been chatting or shifting around in his cot trying to get comfy. He has the tail end of a cold and this all started with him not being able to breathe, but he can now so don't know why he is currently sleeping worse than a newborn.
Any advice on what it could be?
Thanks

Has he seen the GP? Just wondering whether he has a chest infection which can be painful when lying down?

I take it nothing else has changed such as new mattress or anything that might be making him uncomfortable?

No hasn't been to the gp, but does have a cough so maybe I should book an appointment. He naps in his cotbed fine in the day though.
No new anything.