my @exts;
push @exts, $1 while $largeStr =~ /\GTel: 06(\d+)/g;

# or better yet
my %exts;
$exts{$1}++ while $largeStr =~ /\GTel: 06(\d+)/g;

##</code><code>##

print qq[found "$_" $exts{$_} times],$/ for sort keys %exts;