My husband's neurologist diagnosed him over the phone, during the height of the first Covid wave. She asked about his symptoms and when she heard they were obvious ones for PD (slow movement, hunched posture, shuffling, stiff arm movements, soft voice, tiny writing, festinating, falling, balance issues, fatigue) she put him on carbidopa-levodopa. When he responded well to it that was all she needed to confirm PD. At later appointments she watched him move, tested his strength and responses to stimuli. She tried some other medications in addition to c/l but they didn't help much. As I said, he was pretty obvious. If it is less obvious, then they may do an MRI to check for stroke damage or a DaT Scan to check dopamine levels. There are other tests as well for people who have signs of Parkinson's but don't respond to the carbidopa.

This past year I have had bad shaking of my right arm and leg. A little on the left leg. When I try to get into a high chair the leg goes crazy. Same when I have tests that require me to lay. I've had to have assistance in calming the leg. I have the other symptoms. It brings to mind when my dad said he couldn't even hold his coffee cup. I also have the soft voice and tiny writing. Can no longer do calligraphy and struggle with crocheting. My last stroke was acute, so I have worked hard to get as close to normal as possible. I'm regressing a bit. I guess the Parkinson's is making my sleep during the day, memory issues, etc...and have a harder time thinking correctly. I see the neurologist again in a few weeks to get an update.
Your doctor should know what tests to do for you. If they don't please ask the doctor.

It was my husband's gait. He didn't swing his arms when he walked.. I noticed his shuffling and mask face expression. I am a retired nurse. His legs were jumping. It wasn't a very involved exam.

From what I have read, the difference between Essential Tremor and Parkinson's is that with PD the tremor is while the hand is at rest and with ET it is while it is in motion. Also, with PD the tremor usually starts on one side and then moves to the other side after some time. With ET it affects both sides.

Often people don't even notice it when it is just on one side and just when sitting watching TV. With my husband, I noticed his hand shaking when I would reach over to hold hands, but didn't really think anything of it because it didn't affect his life at all. It wasn't until other symptoms became more obvious that we started thinking about Parkinson's. So many PD symptoms are similar to those of normal aging: fatigue, slow movements, stiffness, constipation, etc. Usually a doctor doesn't get concerned until the symptoms have a real impact on daily life.

My only symptom is hand tremors