See the below two links for advices
How can I check if swap is active from the command line?
Why don't EC2 ubuntu images have swap?
A brief highlight roughly from those is this helpful command, to confirm your suspicion:
cat /proc/meminfo | grep -i swap
This will likely provide you with big fat zeroes as below:SwapCached: 0 kB
SwapTotal: 0 kB
SwapFree: 0 kB
How cool is that (without a warning at the very least)...
Watch out when doing memory intensive processing (which is a less than good sign :) but happens), for any reason.