For almost 3 weeks now my baby has wanted constant feeding (falls asleep at breast, is winded, put down, screams & starts rooting as if hungry) for up to 12 hours of the day. He only sleeps (4 hours between feeds) at night (midnight to 8am). Im exhausted and emotionally drained. Not sure how much longer I can continue but really dont want to switch to formula. Have tried expressing but cant fit it in between the feeds\screams. Does cluster feeding really last this long? Any advice?