A key to empathy
The solar plexus has white matter and gray matter, just like in the brain. Gray matter let's you understand things, and white matter lets you feel things. In the brain, gray matter is on the exterior and white matter is inside, so you can understand the outside world you perceive, and feel what is going on inside your body. The solar plexus has the gray matter inside, to understand what is going on inside you, and the white matter outside, so you can feel what is around you (empathy). Abdominal breathing exercises and mantras can help you. To become an empath, you simply need to stay aware and take care of your own heart.
When your emotions are triggered, and you believe it is an empathic reaction to someone else experiencing the emotion, it probably is true, do not doubt yourself. Still, there is an important aspect here that can confuse you. When your emotional feeling is triggered by someone else's emotions, being aware of it does not mean you will feel the intensity of the pain, unless you have the pain for yourself inside. If your empathy is triggered, and the pain comes along with it, then you have an auto-therapy to do on yourself, to let go of the guilt/abandonment/rejection/fear/anger that you hold within you, on your own, without anyone making you endure it but your own self.
Clear empathy will let you be aware of the emotions of others without the pressure of the pain. It is a tool of perception, not a curse upon your own feelings. If you wonder if it is your feeling or not, well, the pain is always yours, but you can still trust that the trigger was empathic perception. We use methods that develop empathy to help us evolve faster. Whenever we feel pain along with our perception, then we know we have work to do, so it is a good help on our path to forgiveness and compassion. Do NOT develop your empathy if you tend to take a role of "victim" or if you already have a hard time living with your naturally uprising emotions.
Breath, concentrate on the solar plexus, resonate the mantra "VURUSHU" vocally, with your mind, and your will power. Vouuuuu-RRRRoouuuuuuu-SHshshshshsouuuuuuuu. Breath abdominally, focus on the solar plexus, open your mind to awareness, don't play the role of the "victim" or the "savior", this will destroy you. Help the people you love without pity, but with integrity and compassion. 5 minutes the first day, 10 the second, 15 the third, 20 the fourth, 25 the fifth, take two days off, and 30 minutes each day afterwards. You will definitely become a full empath. Stop if you cannot take the pressure or you will become depressed.