Why things not go sexually?

Please my female friends answer this
I am 23 . Why things don't go sexually with woman I feel attracted.
Let me share you my story what happened
I was at railway station with my friend. A girls was giving me eye contact she was not smiling but was starring at me not my friend , I approached her and started to talk she was not smiling while talking to me , but after couple of minutes my friend started to talking to her I seen from far , she was smiling , giggling they exchange IDs.
After that I developed insecurities about myself..
Why things not go sexually?
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