First of all, allow me to change the English sentence :
"Am I stupid to be always waiting for you ?"
(sorry, I have to write Japanese in romaji).
You can use "itsumo", but I would prefer "zutto".
[watashi ga] anata/kimi/omae no koto wo zutto matteiru to shitara,[watashi'tte/boku'tte baka to omowanai/ja nai [no]?
 may be omitted.