I think i am low in testosterone?

I am a 19 y/o male I'm 6 ft even maby a lil shorter I am worried my are a bit small for my age . I'm pretty fat I weigh 240 so they might just look small? I have sparse facial hair and I am worried I might be xxy chromosome(small and low testosterone) my seems kinda small as well only 2.5 inch soft n like 5 hard. I'm trippin D: what kind of doc would I see about this and. How much woul it cost I have no insurance and live in the U.S