Hi LO has been on formula now for maybe 6 weeks (is now 20wks and 13lb at weigh in last wk). He screams when bottle finished until burped or filled nappy (which is almost immediate after feed and often just mucus or very mucusy) then is a happy chappy. Had put the mucus now to teething as also has rosy cheeks, nappy rash, lots of drool, is irritable and chews on anything he can find, but am new to formula and am concerned it could be an allergy. I am uncomfortable turning to HV as we fell out due to LO's supposed slow weight gain (forcing me to abandon breastfeeding sooner than I would have liked). Stool sample was normal 2 weeks ago (checked as blood in stools for 2 days). Also early weaning (as advised by GP due to supposed slow weight gain), but it's not the solids he has a problem with (had baby porridge and sweet potato so far). What do you think?