Mystery Plant

Mystery Plant

Observation - Mystery Plant - UK and Ireland. Description: There was 3 or 4 of these small plants under weeds that I found while clearing an allotment! The flo

There was 3 or 4 of these small plants under weeds that I found while clearing an allotment!
The flowers remind me of Balsam and looking online I’m thinking Small Balsam. The allotment has streams two sides and is shady with damp soil.