Running those while shutdown is a waste. You need to wait until after you are off the compounds and esters begin to clear for them to start working. Usually 2 weeks after last injection
There os defintely things you can do to decrease risk, but its certainly a risk of long term HPTA damage at your age. Thays why we recommend no earlier than around 25
There is little to no sides with sarms, so I would suggest 15mg. If you want to start lower thats fine but I wouldnt waste a lot of time at the lower dose as it wont yield the same results
They should have you dialed in to a test dose that doesn't require taking an AI. Thats what everyone means and you are at the high end of normal range right now so test dose might be a little high. What have your estrogen levels been at? I wouod suggest dropping the AI