The general confirmation time is 10minutes(if you have paid the transaction fee), nowadays sometimes the mining of the blocks slow down due to the increase in the difficulty level, so sometimes your tx may take up to 1hour to confirm. To make the confirmations fast you can add a higher tx fee like some 0.001BTC.
The increase in difficulty does not really result in slower blocks, difficulty is adjusted according to hashrate. Highly impossible that there will be a sudden significant slow In block generation due to lower sudden hash rates as ASICs are shipped at a fast rate. Transaction fee of 0.0001 is already enough. After getting one confirmation, any other block generated will result in another confirmation.