Trouble with bottles?? Please Help

Alantra🧜‍♀️ • Wife ❤ 1 son 💙 One on the way with a twin in heaven 💕

My son is 4 months old. Not sure if being a preemie affects this but he was 3 months early. He's only been bottle feeding for 2 months. He's been home from the NICU for 2 weeks now. He's started to eat better amounts than when he was in the hospital and when he first came home. The problem he's having is with the bottles, or nipples I guess. The only ones he doesn't have a gushing stream of milk coming from both sides of his mouth are the NUK orthodontic disposable nipples the hospital sent me home with. But they're only good after so many washes. I even bought the normal Nuk bottles 0 months slow flow. I ordered more like the ones from the hospital on Amazon because the ones I have are getting to be unusable. He's flattening them and they're getting sticky. I also ordered Dr Browns bottles with Preemie nipples.

Did anybody have this issue? How long did it take your LO to be able to use a 'normal' bottle? Is this something that could just be a simple fix or is it a latch/flow problem? I'm hoping he grows out of only using the hospital Nuk soon, or the preemie flow works good for him. It's so stressful because he makes such a big mess and i don't know how much he's actually eating and how much is going down his cheek. I only have 5 left and they really need thrown away but they're the only ones I know he's getting his milk with.