Blockchain.info automatic transaction
You do not understand correctly how does bitcoin network work. Your first transaction was sent to a network and will live there until all it is valid or all nodes forget about it.

Blockchain.info just notifies you that it was not confirmed into a block in reasonable time. Blockchain.info removed it from its memory, but there are nodes on the network which do not forget about it and one of them broadcasted this transaction to its peers.


  Why have both transactions the same ID?


These are not two transactions. This is one transacton, received by blockchain.info twice. First time you sent it. Second time blockchain.info received it fron one of peers.


  Why do Blockchain.info automatically create a transaction without asking the user?


They did not.