Imi, you are not a bad mum, DO NOT blame yourself. Gabriel used to get loads of ear infections,and they were never treated 'cos he'd be a bit whingey and i'd put it down to teething/being tired etc, he had no other symptoms except waxy ears. Wasn't until he was older we realised what it was.
He also woke up one night complainig of earache, i gave him calpol and sent him to bed. He got up a couple of times saying it really hurt, gave him ibuprofen, and was still crying, so was going to call out of hours in morning, he slept till lunch and got up saying didn't hurt so didn't bother. Had paed appt on the Mon, mentioned to him about ears, he checked, he'd perforated his ear drum

how bad did i feel.
Daniel's often picked him up from school with earache taken to Drs and found he's had acute ear infection.
Last time he had earache he also had fluid running ut of his ear (sorry if tmi) i rang both NHS direct and out of hours and all they said was give paracet and ibuprofen and see gp on monday.
Hope Maddie feels better soon

for you both