I'm going to take a leap of faith and assume you are old enough to comprehend very basic logic. I'm usually wrong but several kids your age here have proven it's possible.
If a trainer assists an 18 year old who is doing a cycle, the kid had better at least be someone who has the potential to make a lucrative career out of the sport. Otherwise, the trainer is a piece of shit and probably the one who sold you the drugs.
Do you think it's logical to believe anything a piece of shit tells you, even if it's what you want to hear or how much of a nice guy you perceive him to be? If not, then you should be questioning what you think you know when people who have experience with these drugs give you advice without any monetary incentive attached to it.