If you are weighting to high, if it is costing you to get to run, you should know in that case, it is always better to walk, there will be time in the future to go faster. This happens in the same way as eating, you do not start with the dessert and end with the soup, everything takes a logical order.
A good way to avoid routine when running, is to change quite often the course you do, and if there is no possibility to modify the usual circuit, at least try to seek to make variants of it, use your imagination a little, and you will come up with new alternatives that will allow you to enjoy more your physical activity.
There is no doubt that whoever does sport quite often, (even on an amateur level and whether you enter various types of competitions or not) must take injuries very seriously, and sometimes the only choice will be to stop immediately the activity.
If you are running in an excessively hot day, and you already have done several kilometers, it is likely that the eyes start to itch. Relax! The optic nerve is fine, there is nothing wrong with your vision, it’s just the salt of sweat sliding in the front that has penetrated the eye socket irritating the eye, a bit of clean, fresh water can solve this, although if you start rubbing your eyes compulsively, all you will get in the end is completely irritated eyes
And finally, no matter how long the distance traveled on a given day even when if you improve your personal mark, and no matter how exhausted you are at the end of the journey, the thought that there must always be present, even if not immediately (sometimes you end up so tired thinking that you will never run again, fortunately that thought only lasts a short time), is to get into your head, the objective to improve the mark achieved, even it is only by running one meter more.