Introduction to singing, throat sensation

Hi, I am new at singing technics, have always sung in my car, but now I want to see if I can actually sing something. I have a really low voice, and sometimes I feel some strange sensation in my throat as I  (try to )  hit son higher pitch notes.Is that normal?   I've heard that most of the pressure should be in the diaphragm, so I don't know if I am doing something wrong. if I am do you have any video troubleshooting this. 

Thanks in advance. 

Here's a live lesson we streamed on vocal strain, Alejandro: https://www.youtube.com/watch?v=s6HRdzfpT20.