Emotions all over the place

I’m about 8 weeks and my emotions are all over the place. My husband and I are staying with my MIL and she’s been getting on my nerves lately, I don’t know why but her presence honestly just irks me(I feel really bad for feeling this way). I wear my emotions on my face so I don’t want her to think anything’s wrong or that I’m being a major bitch. Does anyone get like this for no reason????