someone just shoot me...

so on Sunday I was put in charge of everyone at work for 4 hours, doesn't seem that long... I mean it is just 4 hours. but I was the manager on duty and I was the only one that had a managers code and access for 90% of what had to be done. plus Kerstin is still in training so I had her calling me over every 5 minutes. during this time I had a lady come in and pick up her glasses. everything went smoothly (except the fact her mom was butting in every 2 seconds and not letting me adjust the glasses. ) she finally left and came back in an hour. she had a flaw in the lens, it was a small dimple from the coating. I offered to remake her lenses and she was leaving back home to Seattle. she wanted a refund. so I said fine she could have a refund. so i refund the whole amount except the amount for a lens cleaning kit (6.99) it says on the computer that i cant refund the transaction without refunding the full amount, I cant refund the full amount without the lens cleaning kit. so she has the lens cleaning kit down packed in her suitcase. i call Mel and she is in the shower, so i call Becky and she says i cant spoil it we have to have the kit. so I tell the customer this and she flips out. she says she wants her refund and a manager, i let her know I'm the manager. i explain the situation and her mom starts flipping out on me. she finally goes down and gets it and her mom stays up stairs with me and is yelling how riverside vision gives scratch proof coating and one year warranties for free and i should have given her the kit for free and i tell her she should have gone to riverside if she loves it so much. she says that i don't know anything about optical and she knows mores since shes been wearing glasses longer than I have been alive. at that point I'm pissed at her and i tell her i don't have to speak with her because shes not my customer and she has not bought a single item from us. she says I'm making a scene. i tell her no mam your making a scene and walk into the lab yelling good day mam, good day mam! shes stalking me into the lab at that point. finally Mel calls when I'm in the lab and i explain whats happening. she says spoil out the kit or let her keep it and make her pay 6.99 for it(yeah fat chance that's happening). as I'm about to leave the lab her mom is banging on the door and I'm shaking at this point. I want to hit this lady. so i head outside and say nothing to the mom but see the daughter there. she gives me the kit and I refund her the money, i explain I would have been happy to fix the lens and her insurance we billed will have to be notified to so she can have her benefits back. (its gonna take 6 weeks ha ha bitch) so fast forward to today...
the mother called Mel today and said don't believe your employee, believe me. that bitch, she said she got a witnesses phone number and blah. that's OK, i got my own witness statement today and he said i should have called security on her. she also said i picked on her because shes disabled. she says she has problems walking.. she walked pretty good stalking me all the way to the lab. so today at work Mel asks me to go to muchos gracias for lunch for everyone. so i do and on my way back i start balling uncontrollably. i miss my mom, i have some lady saying I attacked her when it was the other way around, and we are financially not doing so well. i am so stressed out. I'm crying so much i fill my sunglasses. i get there wipe my face off and get inside to work.
Travis sees I'm upset and gives me a hug ( i love my Travis) i feel kinda better, but I'm still stressed out. its gonna take a while to get out of this hole.