I got really small payment around 20 k satoshi where i am seeing alert in red color "may be at risk for double spend" even after the transaction is confirmed please tell me is this having any issue for further spend .
if you are talking about bitcoin and also if the transaction is already confirmed and has more than 1 confirmation then you can be sure that there is no chance of double spend. and blockchain.info is just showing that warning because they haven't yet dropped the other (now invalid) transaction from their mempool.
if it is not yet confirmed then it is a different story (but you said it is confirmed so I won't get into that)
