My friends are weird?

So basically I'm in highschool and my friends are always embarring me and I'm like always saying ******* grow up already. I'll give an example one day they were playing with a squishy ball out in the eating area and making moaning noises don't get me wrong I use to do that until 6th grade but now were like all 15 and I'm like wtf. If a girl even approaches any of my friends they will either ignore girls run away or turn all red and say nothing and the girls just walk away and I talk to girls btw. I will not make new friends because I've know these guys for 6 years. I try to convince them to atleast step out of there little spot in the back corner of the library. I am so embarred to be around them sometimes and even people ask me why do I even hang out with them but it's not like I can just make new friends because I'm a very shy person. And advice tips or anything. Also there's this kid in our group that whenever he talks it's like he's screaming all the time and people give us really weird looks because of him. I don't want to be like this anymore.