Bad service at ZARA

I just don't know where to start right now my tears are rolling down,what a bad experience I received at Zara waterfront store, yesterday I bought the 2sneakers for me an my sister, Wich is size4 and size5 ,wat happened is I went there yesterday on my lunch time to buy these sneakers,I found mine on the display Wich is size 4 than there was no size 5 on the floor I asked the consultant to help me out with the sneaker,she went to the back stock room she gave me the shoe it was in the plastic bag,so I went straight to the till points to make payment I payed cash ,for both shoes while was busy paying I asked the lady who was helping me if my there is another colour in that shoe , because it was only green colour on the floor,she told me there is orange as well,since my sister said I must see if there's isn't another colour,I took the photo of the shoe than I asked the lady if I can come the following day if my sister decided with the colour whether she going to take green or orange, than she told me I can come,than I went home coz was running out of time since I'm working in the mall,told myself I will make an exchange following day,I came today at ZARA to exchange the shoe,I went through by the door by the security he sanitised me by the door I went straight where I've got the shoe yesterday,I didn't get the same person was helping me yesterday,but I asked the guy to help me he went to the stock room to get the shoe,than he came back saying there's size in that orange,than on my way out by the door the alarm went on I came back to ask the security to check where's is the problem coz I noticed that already yesterday at sportecene in Capetown it did the same ,so the security check the slip an he said must wait he phoned other security,that's where the problem started they accused me of stilling I had to go back to the shop ,they called the Carlo Wich he's the manager instore,they did up an down there was no explanation on what is going on,but I saw them they suspected me of stilling the shoes I was ****ed shouting,than the Manager came saying I must be arrested,they called mall securities to arrest me,asked them for wat the was no answer they couldn't even showed me the footage, wanted to see the proof of that I did ****** the shoe, there was no footage,they end up giving me the shoe telling me since I'm working in the mall they will call me tomorrow to carry on with the issue after I stand the whole hour, please assist me what must I do with this issue I want my money back I don't want the shoes not anymore,I'll never buy ZARA clothing in my life not anymore ,I never felt so embarrassed like that before , Carlo the manager and Simon the security the treated me as like I stole the shoes,I don't know is it because I'm black I'm looking like I can't afford the shoes,I need answers