Should I follow the interpretation of my istikhara or my heart regarding marriage to my cousin?

I did istikhara for my marriage with my cousin which was fixed by my parents few years back. I have never seen him. I saw that I am at my hometown’s home. I am standing in a room and I was wearing full white cloth (which I had few years back). I was very confused that someone (relative) going to get marry soon or is there any function. Because some of he women, girls had applied henna on their hands and some of them not. Some of them are wearing new dresses some of them are wearing an ordinary cloth. My aunt (phuphi) whose marriage was conducted at my home town and I had attended her marriage ceremony few years back was wearing very old cloth. Then a girl around 6-7 years old came towards me and was wearing sharara which my sister had worn in my aunt’s marriage. She had applied henna on her hands, I maintain a distance with her as if she will touch my cloth it will make stain on my white dress. She again came close to me and by mistake she touched my cloth at my back side of qameez at extreme corner. Initially I felt angry from inside then I thought let it be, it is very small not visible if I will wash it now it will spread as it is wet. When it will get dry then I will wash it and will not make any stain. (I have seen this dream after tahajjud salah). I want to know one should go as per the dream interpretation of istikhra or look in to heart.