If you drink coffee in excess of 6 cups a day it has little if any bearing on amphetamines. Most amphetamine readings are a result of diet pills.
Dopamine is not a drug. It is prsent in your brain as a neuro transmitter. And if you meant amphedamine which i think you probably did, no. amphedamines shouldnt contain coke nothing should contain coke except a few rare combinations such as "starburst", the combination of coke (cocain) molly (MDMA) and special k (ketamine).
Chemicals like Paxil are in a class called SSRI (selective serotonin reuptake inhibitors). Basically, these drugs block the re-uptake of serotonin at the synaptic junction, so there is an overabundance of serotonin. Amphetamines tend to increase the amount of norepinephrine and dopamine at the synaptic junction, not through blocking the re-uptake (like cocaine) but by increasing the outflow from the presynaptic axon.