Two record doesnt fit into each other

[Day-ph]

I am not quite sure if this problem is caused by my bad quitar playing or if it's software problem. The think is that to me it seems that every second track I record is a bit out of the place. In other words it's a bit moved backward. After every second track record when I stop recording I can physicly see the recording shrinking a bit backwards. It may be normal and has no effect on the record but what I am worring about is what if it has some bug with second track recordings? Now I am trying to record two guitar in sequence to make them playing in the same time, but somehow they don't want to sound harmoniously . This may be false alarm. But if anybody's had similar problem let me please know the solution. Thx.