Was with my sick kid at the self checkout this morning

Was with my sick kid at the self checkout this morning. I guess you need to be IDd when purchasing Tylenol now so I scan it and immediately cant scan my next item. I get the message that a customer service rep will be right over. My light is flashing and there's no one headed my way. Right next to me are two ladies just grabbing so I don't think anything of it. All of a sudden one of those two ladies walks my way...at this point im infuriated because I've been looking around for a good minute trying to find someone to help me. She tells me to just give her my birthday but I already had my ID out and im not comfortable giving out my information in public like that. Well I mistakenly had my thumb over the bar code and she rudely told me she couldn't scan the bar code because of my thumb. I then reposition everything in my hands so she can scan it. She rudely says "thank you." Then shes super friendly and nice to everyone else as I finish checking out. My poor sick kid is ready to go and im stuck scanning the rest which took way too long. So rude. So unprofessional.