This made me giggle more than it probably should.
things to portray with teen pregnancies:
Unwanted and unsolicited looks and advice. Idk why but when older people see a young pregnant woman they have to give the "
" and advice about your kid and your pregnancy. I am a woman who looks much younger than my years-
I had 1 semester left in high school when I found out I was pregnant with my first (I transfered schools, there was a “credits” issue and I had to go an extra semester after my graduation to complete the credits they took because they didn’t offer the same classes my old (better) school did.) so I had to deal with trying to hide it from anyone who didn’t need to know because I didn’t want people rubbing on me and bugging me and giving me the “she won’t amount to much” looks. Teachers gave me looks, one teacher even outed my pregnancy—well I did, but I still blame him.
I took a test, and needed to go to the bathroom- again (6mo preg) and he told me no. I whispered my situation as the room was quiet and he still said no. So I left the room for the bathroom and came back to the Vice Principal standing in the class and was ready to give me a suspension until a snatched my ultrasound out and slammed it on his desk. He took one look, looked at me and said "YOU’RE PREGNANT ?! " at the top of his voice. Cut to everyone in the room touching my stomach. 
My second pregnancy, I was eating dinner with my husband ( I was in my 20s) and overheard a woman saying "These damn teenages popping out babies " along with a few more less polite opinions about my financial status and being a “Welfare” baby…
And I, in all my hormonal glory (and much to my husbands amusement. He knows who he married, lol) yelled " I’m 28 you obnoxious dried up twat"-- not my finest moment, but certainly a funny one. I have a mouth that gets away from me- and yes, she was talking about me- I caught the looks and was the only pregnant person in the restaurant.)
So dos: Show the effects you want, but don’t just assume that every woman has morning sickness, swollen feet and cravings for pickles dipped in cookie dough ice cream with flamin’ hot cheetos. It’s simply not true. I was the first of several friends who had children after me and they had much different experiences both physically and emotionally.
Show that the MC has to find a way to work it out and provide for her child with or without the help of others because that’s what being a mother is. Protecting and providing for your child- no matter what you have to sacrifice- friendships, money, time, relationships- a child comes first no matter who or what is happening.
DONT:
Don’t show everyone as supportive. As I mentioned earlier, I do not look my age - and that means that for both of my pregnancies I got the “teen mom” look and treatment from strangers. Even my cousin’s husband (with my first child) told me that I and my unborn child would burn in hell— to which I told him I’d save him the hottest seat.) Strangers judged me as a ‘welfare’ mom- to which I am not, nor have I ever been because even as a freshly graduated high schooler and having my parents give me one of their properties, I had a job, paid for my child and all his things. Not everyone is lucky to have family help and shouldn’t be portrayed as a completely easy process.
Also, for young teens, there is a risk for serious complications in child birth, the younger the girl, the greater the risk – especially in rural, underfunded or remote places.
DO: Show the emotional struggle. Even if it’s not chosen, abortion is something most consider out of fear or need-- whether they go through with it, or from the beginning know that they are going to have their child. Abortion and adoption are things that most (not all) girls consider.
DONT: Show your character as "she knows everything about everything " even if she had a child before-- my pregnancies were 100000000% different from each other. While with my first I had what people called an “easy” pregnancy, I had a very hard, no-medications delivery and with my second, I was the size of a small whale, had all the symptoms and in the last month would have gladly cut my kid out before my back broke. 
Also, with my first, I gained about 20lbs, and didn’t know I was pregnant until I was 3 months along because I still had a period (common in a small percentage of women and stopped a few weeks after I found out)