Being pregnant definitely affects your emotions because of the change in hormones in your body.
I'm sure your husband will understand.
I'm not sure how to advise you because you are not specific on what is stressing you - but be proud that your husbang is standing behind you and trying his best to make you happy and try to adjust to the changes in your body.
I'm 4 months pregnant as well - and let me tell you - I get very stressed sometimes and me and my boyfriend argue as well. But at the end of the day we laugh about it because it was all silly. L