AWS cloud watch "Latency" metric and jmeter "Average" metric in summary report for api performance testing

while load/performance testing of API on ELB in aws using jmeter I see
AWS cloud watch "Latency" metric = 10 ms (seems good) and jmeter "Average" metric in summary report = 3000 ms (seems bad) The API does return 1 mb of json data , but I dont understand why there is so much difference in numbers and is this api performance acceptable ? if the SLA said to have 100 ms api response time .