Is OTHER wrong in the post ? POST : Little backstory:

I work in accounting with about 17 people. The age gap is pretty big. Majority are in their 50s and up and the rest in their 20s and early 30s. Now I absolutely hate when old people treat me and the younger ones like we're stupid but when it comes to computers I am the first one they come to. I have no problem in helping people but I also have no problem in telling people off when they are just nice because its convenient at the moment. Specially older people that think that just because they are old they can disrespect younger people.  

Anyways...

Early today IT guy was helping one of them with something and didn't know how to correct it, so they called me and ask for help. I'm like "am I getting paid for this because I'm not IT" and go about fixing it.  Then I send a little message to coworker saying "I'mma start charging yall $5 for every IT question" (mind you I have been here for 3 years and fixing their IT stuff since I started just because). She then tried to help another coworker about fonts size and she comes around and asks me a question I put my hand out like saying "where's my 5 dollars" she says "I'll buy you lunch" (which probably won't happen) and I tell her what she needs to do so she goes and tried to fix it and here I'm laughing like "wtf are they doing?" They got the other 20 year old to fix it and all is good now. 

AITA for not wanting to help her with IT questions/ fixing issues anymore?