How Should I tell my Parents that we're expecting baby #2?!!

I am 21 and just moved out of my parent's house over the summer with my SO. We have a 5 year old little boy and are doing great. I just took this semester off due to being unable to pay for it but will be returning this following semester. I am going for dental hygienist, but I feel as though my parents don't think I'm taking schooling serious anymore bc of this lost semester. I love college more than anything. I am 4 weeks and 5 days pregnant and am extremely happy. I just don't know how to tell them or when to as I feel like they'll think I'm not in a good place right now to have a baby.

Any suggestions on when/how to tell them? Or any similar situations?

TIA ladies!