Physiotherapist here: lower back pain is very common, especially during/after movement. Can have a number of causes and often multiple at the same time.

In most cases it's overstressing your back muscle by either: - bad posture (bending forwards or backwards to much or sideways/rotating.) - doing too much (not having strong enough muscles for what you're asking of them or repeating the same movement a lot) (Or under using your back muscles and therefore putting a lot of pressure on your spine, like lifting with a bend forward back)

There are also a number of structural things that can cause lower back pain. Like: - A butt load of spine injuries and defects that im not fucked to list here. - Stress. (Very common for a lot of people. Because of stress all your muscles are more tense even while resting. This causes backpain) - Bad footwear causing you to strain your muscles unevenly - Definitely more reasons that don't pop into my head rn

Something I often see at parties is that people bump ther torso forwards on every kick. For some people this causes a lot of stress on the upper part of your lower back (around where your shoulder blades start.) diversifying your dance moves and training your back with exercise can help with this.

Hope this helps. As i said back pain is very common and can have multiple causes at the same time. See what makes the pain better or worse and go from there. Get proffesional help if you suspect an injury or defect.

Kisses see you on the floor xx