something is really wrong with me..

I am 25 & a SAHM of a 4 month old beautiful little girl & a 9 yr old from a previous relationship.. I have a mom who's amazing to me and my girls.. she watches my girls everyday so I can go to the gym and she'll start watching her mon-wed so I can finish my AA... we live together and everyday I pick fights with her idk why I have these anger issues.. i feel like she copies everything i do but it's not literally everything so who cares anyways.. it's even ridiculous things like going inside the bathroom to poo with her phone she didn't do this before until she saw I did but why did it bother me (maybe it's cause I had to use the bathroom and she was taking long cause of it) I also hate when she's on the phone (she's loud) or when her texts come in (she has the volume on like 10000) and I hate when she talks sometimes and doesn't swallow her saliva it's all gathered there and it annoys me I'm like dude swallow and then finish what you're saying... I'm always in a pissy mood and not just her sometimes w my SO too... what do I have ? Am I mentally sick? Do I need to seek help? A lot of dumb shit bother me and I'm taking her for granted here and I know it ... please help I'm at the end of my wits with figuring out what's wrong ...