Warning rant. Is it just my hormones?!

I don't usually post to vent but I just need to know if I'm being overly sensitive. I get really hormonal when I'm pregnant and lose my judgement at times.
I'm 34 weeks preg with baby #3. My other two children are very young still (2 1/2 and 14 months). I'm a sahm and clearly have my hands full. So my mom is a teacher and has had the summer off. She 'needs' to see her babies (aka MY babies) every other week or so or else she misses them so bad. 
Here's my issue: she comes over to visit almost always around supper time, basically making me feel like I need enough dinner for her and my step dad too. Doesn't ask how im feeling if I need anything from the store, need a break, offer to bring something for dinner etc.. Aren't grandmas supposed to know this stuff!? Not her first grand babies either. Wheres the grandma that takes her grandkids for a night or two or even offers to babysit?? Thanks for reading. Maybe I just need a break 😥