You are in 5 weeks? Congrats, dear mom to be! It was hard for me too. I remember I was crying for whatever reason. If there was no stimulus to justify tears, I would just cry at the mere thought of how fragile that baby was and how unprotected. I prayed a lot to God to protect it. It then passed, I am still vulnerable but cry less, and also irritable.
I guess it helped me to think more of the blessing. Oh, and watching comedies and reading funny stuff.
Feed on small pleasures and be strong, don't let sadness get to your baby. Ask your partner for understanding and protection. Tell him what you need him to do. And lower expectations - I know from my experience how much pain they brought me.