Tefilah written complete (תפילה) has the same gematriah as כשרה which is the letters that Eli haKohen saw on the Urim V'Tumim when he inquired about Hannah. We can learn from this that her prayer was true and complete prayer. Perhaps this is why Chazal chose to learn how we are meant to pray from Hannah. (חנה)
What does one yud more or less matter? Yud is a single point, a complete unity, Chazal tell us that kedushah, holiness, only resides in the presence of the number ten. (In the case of Jews, ten is a minyan, a quorum, in which the Shechinah, the Divine Presence, always resides) If you don't connect your prayer back to the unity of creation, then it is lacking something.
Given all this, if song is how you connect to HaShem, then keep it up. There are many paths to holiness, and all of them start with where your heart yearns most.