Early flowering blackthorn?

Early flowering blackthorn?

Observation - Early flowering blackthorn?. Description: Collection of small 5 petalled white flowers on bare, thorny twigs and branches. Confirmation of identification neeeded for addding to 'Nature's Calendar'

Collection of small 5 petalled white flowers on bare, thorny twigs and branches. Confirmation of identification neeeded for addding to 'Nature's Calendar'