I do believe that if you don't do everything possible, you may well be asking "what if" should, heaven forbid, things turn tricky at a later date. It's best to ask about absolutely everything that goes through your mind and give your reasons for asking.
If you feel you should have a second opinion, then go for it. It's your life and you are entitled to do all you can to preserve it. Any doctor worth their salt would take time and patience to explain your options and take into account your preferences. If they don't cooperate, then you are best off going elsewhere.
I do understand it's hard to fight your corner when you are ill and anxious but, when you are better and look back on this time, you will feel so proud of yourself.
All the best!