After a blissfull week of sleeping through our almost 6 month old DS has started to cry during the night, however sometimes he appears to still be asleep. The last two nights this has started 50 mins after he is put down at 7pm. Picking him up at this time seems to help - but he will still cry for a while in our arms and then once settled I have put him down. Last night he also started crying approx every 45 mins - 1hr after this until being fed about 1.30 when he was properly awake, he then slept through till 7am. Some of the crying before this point was only brief and he went back to sleep again himself. When I say crying - I also mean proper crying rather than grizzling.
I just really want reassurance that he is ok and that I should not be worried that he is crying but appears to be asleep. Any advice gratefully received.