Instead of being frustrated, may I suggest you consider this. The time you devoted to this research. Was it because the subject held your interest or because the information you sought was not readily available? if it was interest, then you should be pleased you found such a unique topic. If it was difficult to research, congrats on "staying the course" and committing to the task at hand. Either scenario reflects well upon you. Best Wishes

Agreed! I do the same thing. It helps if I set a definite goal for what I wish to accomplish at the time and limit the distractions as much as possible.

Frustration with yourself for not meeting your goals is something we all deal with. I treat it like water off a ducks back. Let it flow and try to go easier on yourself.
Revel in the things that you were able to accomplish and don't dwell on the fact that you set yourself an unrealistic goal.

You are quite right we all get caught up in this scenario, the longest I ever did was 42 hours straight off - never again. Seriously though, this teaches two things. Firstly, prioritise to see where you will get the most benefit from in the tasks that face you each day, and if the most important one takes more time than expected, so be it because you will feel good at achieving this task. Secondly if this happens then we need to be flexible enough to re-schedule the remaining tasks to take account of the time overrun. Don't let this get to you because if you do your attitude to the rest of the day/work will not be as positive as it could be. Look for the achievements and let these boost your ongoing attitude to the next task. Note that in my case in 42 hours, three days tasks got put on the back burner, but the one in hand was important!
Hudson.