خلينا is in second person singular (المفرد المخاطب) and خلونا is second or third person plural (الجمع المخاطب أوالغائب). In certain contexts it makes a difference, for example:
المعلم خلانا نروّح بدري
المعلمين خلونا نروّح بدري
In others, as in the examples you gave, it doesn’t make a difference. I can’t tell you when it makes a difference and when it doesn’t, I’ll have to think about it a little, perhaps others can help.