Mother In law trying to cross the line

My son is 11 months old and my MIL is always going over the top and trying to take control .. for example a few weeks ago my son split his lip open and being a Sunday afternoon I said to my partner we need to go to the emergency room I think he needs stitches and he told his mum which then texts him every 20 seconds saying you should have called me show me his face send me a video don’t let them stitch it what is the doctor saying and so on literally within a 5 minute time frame then while seeing the doctor she wanted a video of him in distress and crying .... to see what the doctor was doing to him ... all the doctor did was look in his mouth to see if it punctured through which thankfully it didn’t and she was able to glue it back together and he was only crying and upset because I had to hold him still while she did did that ... then on the way home still messaging saying how she wishes he called her and all that.

I ended up getting annoyed and said to my partner what difference would it have made she is not a doctor she does not decide what is best for him and if he ever hurts himself and you call her over me or a doctor I’ll be absolutely fuming... so continue a few weeks forward and my son comes down with a cold and tonsillitis she’s messaging my partner telling him what I should do this and that and everything under the sun when I had already taken him to the doctor done everything the doctor had told me and also had him in bed with me for the night to watch him ....I told my partner I’m quite capable of deciding on my own what my child needs I’m not stupid I can take care of him I do take care of him 99.9% of the time on my own and he just says aww she just cares and brushes it off.

I feel like she wants to control every single thing to do with him and tells my partner things he should do behind my back and his whole mothers side of the family act like he is her child and ignore every single thing I say only ever ask her how he is or if he can have certain things just basically treat him as her child ... it drives me absolutely mad and it’s extremely hurtful especially because my partner will do the same and listen to everything she says and try to override my decisions which is not ok and I’ve told him this but he doesn’t listen.

I feel like one day I’m just going to loose my shit and be made out to be the worst person in the world -.-