baby spitting up

Hello ladies, I currently have an almost 1 month old baby boy and I have some concerns. He is currently BReastfed and bottle fed (at times) I feel he has some kind of acid reflux or so and after some feedings he spits up but when he spits up the milk shoots out his nose as well. Has this happened to anybody else? He also hasn't pooped in a day, he does burp and pass gas throughout the day.  The formula he is currently on is the enfamil gentle and I'm thinking of switching him to the gerber good start gentle, any suggestions?