All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
You may perform the Istikhaarah prayer once again. The scholars of the Maaliki and Hanafi Schools of jurisprudence are of the opinion that repeating the Istikhaarah is desirable since it is a kind of insistence in supplication which is beloved by Allaah. It is reported from the Prophet that "whenever he supplicates, he repeats it thrice, and whenever he asks Allaah he repeats it thrice." [Muslim]
The Istikhaarah prayer is legislated to seek Allaah's Help and asking Him for what is better, so if the person who performs the Istikhaarah does not feel tranquility and peace of mind, he may repeat the prayer so that he feels at ease and feels tranquility for doing something.
Imam An-Nawawi said: "One should do what he feels comfortable in doing; therefore, he should not rely on something he feels comfortable with based on his desires before the Istikhaarah. Rather, a person who performs the Istikhaarah should give up his own choice, otherwise he does not perform the Istikhaarah to Allaah but performs the Istikhaarah to his own desires. He may not be honest in seeking the Istikhaarah and in confirming the Attributes of Knowledge and Power to Allaah. If one is sincere in praying the Istikhaarah, he declares himself lacking knowledge and power as well as (leaving) his own choice."
To conclude, it is desirable to repeat the Istikhaarah if one does not feel comfortable and does not feel tranquility at the first place.
Allaah Knows best.