cheap flights, bags etc.

booked cheap,now regrets,only 7kg inc bag,no extra carry on Hainan and Etihad return. Think the bag alone is 5kg,but my overcoat weighs 20 kg,deep pockets,plus light jacket must weight 10kg, Anyway see if I can get away with it,if Id waited another few days Gulf and others now at £533 return ,plus checked bag