I'm no medical expert but I will throw in my two cents worth based on what you've written, which is solely my interpretation.

Let's try separate the facts.

You bought your mom a cooker. What a lovely gesture. What was the intention of doing this? Did you want to surprise her, spoil her, show her you love her?

Now somewhere in between you handing over the new cooker, which is a great thing to do, you suddenly began questioning her feelings for you.

This was after you had given her the cooker.

So I'm wondering if you can recall, a specific "trigger" that happened during this time frame that suddenly set you off. Have you had self doubt in the past about your moms feelings for you? Was giving her the cooker a means of you showing her you love her? Is there something about her reaction when you gave her the cooker that suddenly sent your brain into a frenzy?

Have you in the past, prior to this experience, had conversations with your mom about are you okay, are you mad at me, did I do something wrong etc?

I don't believe, quite honestly, that she wants to kill you over a cooker!

It's something else.

I'm playing devils advocate here to explain that there might be a different side to the story. Maybe you do upset your mom when you think she's mad at you etc etc - not because of how YOU feel but because of how SHE feels. If she's bought you up from birth, and loves you unconditionally could it be heart breaking for her that her daughter has these feelings of self doubt? I don't know what your relationship was like growing up with her but maybe there's a part of her that believes she did the best possible job that she knew how to do at the time? So maybe she gets upset when you think that she is mad at you.

I think your subject line with the word "paranoia" is spot on. I tend to over analyze things - people, situations, events .... That sometimes turn out to be not real.

So ask yourself these two questions:

Is she really mad at me for buying her a slow cooker?

Or is she an upset mom because she's done the best she knows how to do and doesn't understand where these feelings for you are coming from?