Discovered it this morning. Red, flat, non-itchy, goes away under pressure (phew). No fever, feeding well, alert, bit unhappy and unsettled but mostly fine when held. Been to out-of-hours doctor who can't say what it is. Tbh it looks allergic to me but he is excl bf, bathed in plain water once a week, haven't eaten anything unusual or used a new type of washing powder. Teething? (Is showing other signs thereof). Virus? (Has had a cold for a while, there seems o be a slight resurgence). ???