Timecrimes (original title "Los cronocrímenes") uses a model of time travel where the future is already fixed and cannot be altered. Anything a time traveller does after travelling into the past had in fact already happened even before they travelled back, whether or not they knew it.
The example given in some physics books is one of an object being knocked into a wormhole after collision with another object. The wormhole carries the object into the past, where it emerges and crashes into its earlier self, thus becoming the reason it was knocked into the wormhole in the first place. The events of time form a closed loop, and even where time travel could be expected to change things, it in fact creates and closes the loop.
In Timecrimes, Hector knocks himself into the wormhole, scaring himself towards the time machine. Everything Hector does is driven by his own actions, and even when he finally appreciates this he realises he is unable to break out of the mess he has made.
Because we have followed Hector the whole way through his time travels, we know that he never bumps into himself on the chair outside the house at night. Which means we know that none of his previous incarnations will meet him there. So long as Hector (finally) stays away from the time machine, the loop will close and the other incarnations will disappear (via the time machine) so he will not have to worry about them any longer.
What he does after that is indeed speculation. He's certainly made a real mess of things, and
even with his wife as an alibi, he is going to find it hard not to be blamed by the police for the murder, given that forensics will find traces of him all over the crime scene.
In the short term, I'm guessing he just sits on the lawn chair, catches his breath, and curses himself for disobeying the clear instructions he was given at the start.