How can feelings just be molecules in your brain

So the universe is essentially made up of a large number of sub-atomic particles in an infinite sea of empty space. These particles make up atoms which make up the molecules that make up your brain. But then all your brain is is a few trillion molecules grouped together.

Any positive or negative feelings or emotions produced in your brain that you feel in the end are just a bunch of molecules moving or reacting in a certain way. How can something like a feeling be represented by mere particles? What's stopping your brain from just being an extremely complex computer?

They say pleasure is created by your brain by the 'release' of certain chemicals, dopamine for example. How can a group of atoms bonded to each other in a certain way create the feeling you get when you're say happy. Or any other emotion.

Just think about the last time something felt really good. How could that feeling you're imagining right now just be a bunch of particles, essentially just three dimensional dots, arranged in a certain pattern?

I can understand how the molecules in your brain can combine to make complex decisions, just like a computer can perform calculations using nothing but electronic positives or negatives. But how is something like a feeling or an emotion nothing more than a group of particles in your brain. What's stopping your brain from being just one large mathematical equation that adheres to the laws of molecular chemistry.

Jesus christ that was long winded.

Feeling are all biology, which reduces to chemistry, which reduces to physics. Believe it or not, your feelings really are caused by a release of chemicals in your body. A very brief example: physical contact stimulates the production of oxytocin, which causes feelings of comfort and closeness. That's why hugging and holding hands is used to promote bonding.
If you think there has to be something more, google "qualia".

Key is electricity. The nervous system relies on the conversion between electrical signals into chemical signals/neurotransmitters. These processes take place in neuronal synapses. This explains why you can make dead muscle twitch just by applying electric charge to it.

Its difficult to answer how it works-what you will find is most neuroscience research looks at what functions are gone if you remove/temporary inhibit the function

i.e. if you inject saline at X point you can temporary induce Y function-> from this neuroscientists can infer what that section of the brain is involved, the problem with this is you can have whats called a double dissociation, when two people have similar lessions but have different loss of function.