Hihi~
1) This sentence has no mistake but using: "we were both alone before" will be better.
2) Using: "We know about love now" will be better.
3) Using: "Warm-baked cookie in christmas" will be better.
1.Very good!
2.It's okay but I think you use 'we know about love now' is more good.
3.Don't use warm!!Because warm is mean'暖' and you can use'Baked cookie in C(must be capital letters)hristmas'.