15 and pregnant...? HELP 😰

I know this might sound a little odd, but I wasn't sure what group this would fall under and I really need help from at least one person .😫 so please if you can , just take a little time to read .
I am 15 , I have a boyfriend who I love very much and have happily been with him since the 7th grade . He is one year older than me, and we became sexually active about a year ago . At first we never really had sex a lot , only every now and then. but recently about the last 4 months we've been having sex every single weekend . About half the time with no protection, (dumb , I know) and recently I've noticed that my period was late by a week , so we took a test and it came out negative . But since I took that test, I still have not gotten my period. I have not had it all of may and according to the app, I am 28 days late . THIS HAS NEVER HAPPENED BEFORE. I've always had regular periods, and I tried not to stress as least as possible so my period won't be any later. So , my boyfriend said we should take another test next week if it doesn't come by then , and go to our local pregnancy center. But the thing is, I have no idea what to do, or what I need to know to go to the pregnancy center . I don't know my own insurance , I don't even know my own social security  . My mom is the one who keeps track of all that for me , and if I were to ask her she'd ask why and I really don't want to tell her unless I absolutely HAVE to . So if someone just give me some advice about any of this , anything in this whole paragraph , that would help a lot .  And possibly if it's not too much to ask for , maybe I could text one of you just if I have any questions . Thank you 💕
DISCLAIMER: 
No, I was not planning to have a baby at my age . But both me and my boyfriend are good kids . We have good grades , we don't drink, smoke or party .  we BOTH have steady jobs and we each bought a car with our own money . So if you are going to bash me at all for this, I don't want to hear it . I'm sorry, I'm only 15 but I know where I went right and wrong and I just need help and advice at the moment . No more negativity .Â