It’s okay if she gets a lip blister, they don’t usually mind them
It might not be the formula, you should look at pace feeding as she might just be getting it too fast
I was having a similar issue with my little boy. He’s a month old now and has been formula fed since birth (for multiple reasons). He has always eaten a lot and was guzzling down formula super quick and then would be up crying from being gassy and would be throwing up milk. We tried gas drops and they didn’t work. We tried a couple different formulas too and found that Enfamil GentleEase has helped. That’s what he’s current eating. Some other things that helped were only feeding with the Dr. Browns anti colic bottles and slowing down the feed. Taking the bottle out every couple minutes to let him process and calm down. I also try to burp him at least twice throughout the feed and then again when he’s done. This has drastically decreased how gassy he gets and is not spitting up as much as he was before.
Pace feeding them helps with the gas. Pausing to burp them every oz or so when they are that little also helps as their little digestive systems are still so immature also trial a different bottle in case the one you're using doesn't suit her and she's getting too much air x
I would definitely try pace feeding as 5-10 mins is really fast and probably explains why they are gassy and sick! Also maybe worth trying a slower/smaller teat size so they don’t guzzle it down!
I do the same exact thing as @Arianna ! My LO chugs it too!! I slow down his feeding, take breaks, try burping in the middle, take a break, change his diaper which will usually wake him up anyways, feed again, burp again and sit him upright for a bit. It’s reduced how much he spits and throws up and I also give him enfamil gentle ease. The whole process of feeding and diaper change takes me about 30-40 mins depending if he’s being very fussy.. this has helped
Try pace feeding and wind her every couple of ounces or so also check the teat flow size isn't too much for her.
Slow down the feed. I would feed my girl. Stop for a min and then start back up. Stop and burp her. And do it frequently. Feed 1 min. You can change the nipple on the bottle.