First pregnancy! Excited and Scared!

Im 19 and my bf is 20. First baby. Im excited. I am 6 weeks and 3 days. We've been together for 4.5 years. Were not planning this and I've always said I didn't want kids and honestly was thinking of not keeping it but today I realized that I have to. That it's a beating heart and I wouldn't want to miss out out the chance of meeting this creature we've created! I have always been afraid of birth and mostly to tear during birth. Any suggestions to facilitate or to not tear? I was thinking giving maybe giving birth in water maybe? Any feedback or advice is appreciated! Thanks!