Asked and answered. This point is meaningless.
First, no true prophet would ever have to testify regarding himself that he was a prophet: Jesus said, "If I testify about myself, my testimony is not valid" (John531). So, if you think that Jesus sounds like a prophet, understand that the words of Jesus basically mean that Muhammad could not be a prophet for he testified with regard to himself.
Second, there are many who testified with regard to Jesus. Among them John the Baptist, Thomas, Peter, Paul, and even God himself.
Third, when people treated any of the disciples like God, they all refused such treatment. When people treated Jesus this way, he accepted it. If he was just a prophet, he was a poor one for accepting such acts.
Fourth, whether Jesus ever used the words "I am God" or not we will never actually know. He may have, for not all of his words are recorded in the scriptures. But even if he didn't (and I expect that if he had they would have been recorded), his actions and the things he did say were understand by those around him to be equivalent to him to have made divine claims for himself. He claimed to forgive sins. He referred to himself as being one with the Father. He declared, "before Abraham was, I am." These things led others to accuse him of blasphemy for equating himself with God. When asked to recant such accusations, he did not, but accepted them.
Fifth, Jesus pointedly asked people to receive from him what only God has the ability to offer -- life.
Sixth, Jesus claims to possess a position alongside God in a way that no Muslim would ever be able to either acknowledge of any human, and that no one who was a true prophet and only a prophet would ever claim:
Seventh, Jesus never says that he is NOT God. And though Jesus may not have said "I am God" in so many words, others did say that of him (see Thomas' confession in John 20:28), and Jesus praised them for it.
Also, the scriptures record God saying that Jesus is God, see Hebrews 1:8.
You can argue all you want from an Islamic perspective that Jesus is not God, that God has no partners. But you have to stay with the Islamic scriptures to maintain that point. The Christian scriptures say otherwise. And if you try to twist them into saying that Jesus was only a prophet of Islam, then he is the most intersting prophet of Islam claiming that God was a Father, that God has a Son, and that somehow not only was he a partner of God, but that he invited his disciples (who are clearly human) to become partners of God as well and to one day not just join him in paradise, but to even share in God's glory.