No not always, here s an example if your involved in a crash the body will release chemicals causing an increase in vitals such as heart rate and blood pressure so the tissues can get better oxygenated and the body can work better under a stressful situation. At the same time if you were to suffer an injury during that crash which caused you to lose blood volume resulting in a decreased blood pressure the body would try to compensate that loss by increasing your heart rate. The same thing also happens in dehydration and a few other ways.