Why did he mention "you came yesterday"?
Malbim: [If you seek to help me -] you will be tired and weary (for you just came, and you will need to relocate constantly).
Why did he say "veha'Yom Ani'acha Imanu"?
Rashi: I have no place to settle you there, and you will escape. (You will need to constantly relocate. Refer to 15:20:4:1.
Why is Ani'acha written with a Vov, and we pronounce it with a Yud?
Radak: Both of these are similar, just it is written in a Kal conjugation (you will be moved around), and it is pronounced in a Kaved conjugation (I will cause you to be moved around).
Why did he say "Al Asher Ani Holech"?
Rashi, Targum Yonasan: I go to wherever I happen to chance upon each day; when I hear that the pursuers are here, I flee here. Radak - Al is like El, e.g. "va'Tispalel Al Hashem" (1:1:10).
Malbim: I do not know my destination. I go to flee!
Who are "Achecha Imach"?
Radak: They are the 600 men who came with you from Gas.
Why did he mention Chesed and Emes?
Rashi: I appreciate the Chesed and Emes that you did with me.
Radak citing Targum Yonasan: Return your brothers with you, and do with them Chesed and Emes.
Malbim: You should return Chesed and Emes to the men who came with you, and they should not need to constantly go to and fro.