yes
These could be signs of pregnancy or miscarriage.
Only the tiredness is a symptom of early pregnancy, so it is probable that something else is the cause. You could repeat the test as it would be very unusual to get a false negative at this stage. Then you should consult a doctor to find the true cause.
Most climbers die during their descent. This is usually due to tirdness, lack of energy, feeling cold and hungry.
It can effect everyone differently. Some people it can be seen externally e.g. hair loss, spots, weight lossand others it is internally e.g. depression and tirdness. With everyone though they are at a higher risk of getting ill, if you are exremly stressed you are 50%more likely to get ill than a normal person.
Arms may ache for a variety of reasons, such as, diabetes, neuropathy,vitamin deficiencies, trauma- physical/thermal/chemical, inflammation, bad posture, accumulation of metabolites like lactic acid etc.If you are an inveterate computer user, or use a typewriter often, your arms may ache.