Why does my dog follow me everywhere?
Quick answer
Usually affection and habit rather than anxiety. Dogs are social animals and follow the person they bond with most. It only signals a problem if your dog panics when left alone.
A dog who trails you from room to room, including into the bathroom, is usually paying you a compliment. Dogs are social animals, and following is a normal way of staying close to whoever they are most bonded with. Often you have accidentally trained it too, because good things tend to happen wherever you go.
There is a meaningful line, though, between a dog who prefers your company and a dog who cannot cope without it.
Ordinary attachment
This looks like following you around, then settling nearby and dozing off. Your dog may notice you leave the room and choose not to bother getting up.
Separation distress
This looks different. The dog becomes agitated as you prepare to leave, cannot settle at all when alone, and may pace, drool, bark persistently, scratch at doors, or toilet indoors despite being reliably house-trained. Many owners never see this, because it happens after they leave. If you are unsure, record a few minutes on your phone.
If it is ordinary attachment and you would simply like more space, reward your dog for settling on their own bed rather than only for coming to you. Give them something absorbing, such as a food-stuffed toy, while you move around the house.
If it looks more like distress, the approach is different: building tolerance gradually, starting with departures so brief that your dog never becomes worried. This is worth doing with professional guidance rather than alone, because pushing too fast reliably makes it worse.
Sudden clinginess is worth noticing
A dog who was previously independent and becomes attached seems sweet, but it can be a signal. Dogs often become more clingy when they feel unwell, are losing their sight or hearing, or are experiencing cognitive decline in older age.
When to call a vet
Speak to your vet if clinginess appears suddenly in an adult or senior dog, comes with restlessness, night-time pacing or confusion, or if your dog injures themselves, damages doors, or cannot be left alone at all. Separation anxiety is treatable, and worth involving a vet or qualified behaviourist rather than managing alone.