Age and compatibility

Hey there! Me and my so are 4 years apart 17 & 21.. We found out that we where pregnant 3 weeks ago and I'm just having a hard time with everything. I over think everything but usually come to terms with it but this is hard because a baby is obviously a lot of work and a lifetime commitment. It's not that I don't think I'm ready because I know I'm fully capable of doing it but I'm independent and Idunno I just want to know if anyone has been in my place. I feel alone right now for some reason