Relax... this is what most people tell you if they see you being stressed or almost out of your mind. Don't get me wrong, relaxing is a good thing but you have to know the difference between purely relaxing and relaxing while doing something.
If you are so busy, stressed and it seems like your heart will explode because of too much pressure, people will tell you to relax. But what does it mean? it means you have to control your emotions, stop rushing and breathe deeply. You have to find yourself and stay calm. It doesn't mean you have to play dota while working at the office, it doesn't mean you have to smoke 12 cigars right away and forget your work.
Real relaxing means you just have to be aware of what is going on, you can't be totally forcing your work and expect results to come out good. If you are constantly pushing and rushing then the output of your work will become ugly. You need to gather your energy, run your true pace and let things take care of itself
Be quick but don't rush, be cool but don't slow. Sometimes people tend to forget to breathe and feel their life, they push and push and push only to wear themselves out in the end. You have to constantly remind yourself that it is just work and nothing more than that. You have have to be serious about your work but don't consider it as the only source of your life, You can live without it so don't worry if you feel you cannot finish it, just keep moving and work until the end.
Relax but don't relax like a bum. Don't take your work for granted, make progress every now and then but don't ever let pressure enter your system or destroy your mindset. Remember that it is just work, your boss cannot fire you if you are doing good. Nobody has the right to push you, only yourself has the authority to push you.
It feels good if you are working in your pace, it feels good if you are working relaxed because good things will come, the right decisions will be made and of course you will not be stressed.
You can push a little bit if you are really into it, but don't push because you are scared that you might not finish your work. Always remember that your work is just giving you money, it is not giving you life.