Is it normal for a shower to drip for a period occasionally?

Hi,

We recently had a new bathroom fitted which also involved a new shower. I've noticed that the shower occasionally will suddenly drip for a few moments (maybe 10 seconds, maybe longer), despite water not being used. It only happens from time to time (maybe a couple of times a week) and then stops, so it's not really a big issue.

I have a one year guarantee with the builders, so if this is something I should be concerned about, do I need to ask them to come back? Or is this just a normal kind of thing with some showers (our plumbing is ancient - it looks like spaghetti junction where our water tank is).

Thanks in advance.

 

Thanks. Yes it's just the shower head - taps not affected. Is that good or bad?

 

Thanks, much appreciated.