tomato fruit seemingly too small

I'm a first time tomato grower. My plants are of the Sweet Million f1 variety, so they are a cherry tomato plant. But the fruits have appeared and are only a cm or so.

My plants have had a lot of stress - nearly drying out, being knocked over by the wind. I;, watering them daily - it's so hot and the leaves look like they are wilting. The remaining look like they have blossom drop but they all looked like this and most have fruits. I am feeding once a week.
is there anything i can do to ensure maximum size?

Thanks in advance

 

Are the tomatoes ripe? Cherry tomatoes are small anyway and if they're still green they will have some more growing to do. Mine start off tiny and are quite big now, even though I should probably give them more fertiliser than I do.

 

The only thing that makes me worried is there are larger ones beginning to ripen on the same trusses as miniscule ones. how often do you feed?

 

My trusses have small and larger tomatoes on because they were pollinated at different times. I meant to feed my tomato plants once a fortnight but that doesn't always happen!