Good evening! Girls, can anyone tell me what happened? Sneezing and s...

Good evening! Girls, can anyone tell me what happened? Sneezing and slight temperature appeared. Sneezing passed on the third day, temperature was 37.3-37.8. It went away in a day and a half. And today the child has been breathing through his mouth all day. When he sucks on the nipple, he breathes through his nose. I listen to his breath, no wheezes or phlegm is heard. Breathing is even. But he breathes mostly through his mouth. To the doctor only on Monday. What could it be? And what can help until Monday? At night, not just humidifier but also wet towels, and with a spray bottle everything goes through.