without a closer shot of the suspects, I won't hazard a guess but will offer this bit of advice...
buy a jewelers loop, 10X and 20X magnification...this will allow you to see any insects on the plants...there are several pests that simply can not be seen without use of magnification...the jewelers loops are cheap and will give you some piece of mind...
https://www.google.c...iw=1536&bih=783
Red Spider mites are very hard to see on the plants since they are only about .5 mm long and I simply can not see them on the leaves...if you take a piece of white notebook paper, hold it next to the leaves that are suspect, brush your hand fairly quickly across the leaves towards the paper, you can collect most of what is on the leaves...then look at the paper....if you see any tiny red dots moving on the paper, you probably have red spider mites...this also works for thrips...I don't have an issue with aphid identification because I can see them...