Filling loop - small leak after repressure

Hi all
I bled a radiator today and had to top up the pressure on my Glowworm 24cxi combi.
After I closed the valves and turned the heating back on there was a slight trickle of water from flow side of the loop. Couldn't see exactly - but not the valve itself, somewhere above it.
Just a few of teaspoons worth. And an hour later, no further signs of leakage.
Happened a few months back after I moved in and bled a different radiator and topped up. There were no leaks afterwards and it had a service shortly after with no problems detected. Stupidly I forgot to ask the engineer about it at the time.

Anyone had this problem before? Should I get someone out to investigate? Boiler is about 10 years old.

Photo attached. Thanks in advance for any help

often washers dry out and when they get wet seal themselves , dint worry
centralheatking

May be a small drip inside the boiler. If you are worried give a local engineer a call.

Flow link inside the boiler is notorious for leaking on them. Particularly when repressurising.

You will need a registered engineer to check this

Cheers