Sandra,
One thing I left out in my 1st reply. . . I'd bet your guitar playing did not start at the level at which you are currently playing, so keep in mind you have just started the singing journey. You will get better with each practice session and performance as you are a too good musician for that not to happen and that will without a doubt in my mind, translate to stronger vocals.
Edited portion: Remember Herb Alpert, strong trumpet player? I also remember that while he was never know for his voice his heartfelt rendetion of
This Guys IN Love With You was a big and memorable hit.
Later,