When i'm feeling very stressed (usually about my job) my heart will ache, back will hurt and my sides cramp. what can i do to cope with the stress ?

Many things!: On your own, you can practice present moment awareness as with meditation, yoga, tai chi, qi gong, etc. Also eat healthy whole foods instead of processed ones; eliminate caffeine and other stimulants. Get consistent sleep & exercise. You can also meet with a psychologist or other therapist to explore your stresses, and see any patterns you might be able to change in helpful ways. Massage too!