I'll try to limit the spoileriness of this post
Clearly what is happening is a predestination paradox, where Cole's time travel caused all of this to happen in the first place.
I am struggling with the watch paradox. Somebody help me out here:
Cassie has a watch (2013?) Cole gets Cassies watch from his time and brings it back with him (2043) Cole brings the two watches together to save Cassie (2015) The watches eliminate them selves. things go boom, Cassie is saved. (2015) The watch no longer exists. so It could't be there in 2043 for them to bring back.
I am okay with this series of events except that I can't reconcile it with the predestination paradox.
The watch no longer exists(2015) Cole can't bring the watch from his time to 2015 Cole cant bring the two watches together, to save Cassie. Cassie dies, No message, thus no time traveling Cole.
It seems to me that the only way to escape a predestination paradox would be to use one of these (elimination?) paradoxes.