You don't need a plumber Ric.ror........... not a lady of your capabilities ;o) If it's not an airlock, then the washer has stuck down on its seat over a period of non-use. Turn it on and tap the body of the tap to see if you can dislodge it.
Failing that, ask the nice man next door if he has an adjustable spanner to unscrew the valve body to have a look inside. (For this, turn the water off first.)