Crying for no reason?

MomOf2 • Married 💏 DD:4yrs old 👑 Angel Baby 5/6/2014 👼 My Rainbow Baby! 5/21/2015 👶🍼💙
Idk why, I keep crying for no reason... I don't know if it's the stress I feel sometimes, like especially when people come visit (which I have restricted to only CLOSE family : example my mom, sister, and in laws). I still feel super stressed when they are here, I cry when I see my baby, Its happy tears, I get so happy! But at the same time, I lost my baby a year ago, may 6 2014. I feel so protective of this baby because I feel as if I need to overprotect him since I lost my other baby. I just don't know if I should keep crying it out or actually talk to a doctor about it? I talk to my husband about it, and he reassures me that our baby is safe and sound with us and that I'm doing a good job. 
Also breastfeeding hasn't been a walk in the park, I gave into doing both breastfeeding and formula and I feel so bad for that. I feel like a bad mom for giving my baby formula and breastmilk. 
I just hope things get easier, for now I have this app to at least write my feelings. 
Thank you for reading. Xx