Help with some Beginner Code? - Small problem with entering text.

[Dr Quack]

Hey VBForums. Hoping you guys can help me out with solving a small problem I have.

Private Sub GuessTextBox_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles GuessTextBox.TextChanged
        If Not IsNumeric(GuessTextBox.Text) Then
            GuessTextBox.Text = ""
            MsgBox("Hey! Letters don't count. Only numbers")
        End If
        If IsNumeric(GuessTextBox.Text) > 1000 Then
            GuessTextBox.Text = "1000"
        End If
    End Sub

I have this here, i'm making a simple 'Guess the Number' Kid's game.
If the user enters a non Integer number in the 'GuessTextBox' it will give them that message and erase the number in the box.

Every time the space becomes blank however the message prompts.

So if I type 125 then backspace it, it will give the message. How do I make it so this message only prompts when something non-numeric is placed in?

OR Is there a way I can make it so it simply doesn't allow anything but 1,2,3,4,5,6,7,8,9,0 in the box?

Thanks.