My son was breastfed until 14 months as i gradually weaned him off the boob. Since then hes had the occasional feed normally when hes ill. However about 10 days ago he seemed to be getting a cold so i fed him and thought it would be a one off but since then hes been feeding for half an hour each night! Ive tried to be stricter but last night he was hysterical so i gave in. What can i do?