Thanks for the help & information so far.
I guess it makes sense that the pins are influenced by surrounding noise when they are floating.
As suggested, I wanted to test my pins by connecting several potentiometers. I only have two potis , but I connected them. Then I noticed the strangest thing. The first poti worked fine and values in my Serial monitor corresponded correctly. When I tried the 2nd poti the serial monitor froze and my Arduino was not recognized by the COM3 serial port. I tested this again and the error reoccurred. I noticed that this not specific to the pin but to the potentiometer!!!!! Whenever I use this one potentiometer my Arduino loses serial connection!? What's going on???