What is happening to my cucumber plants??

Hello everyone, can anybody advise me on my cucumbers please. There are these spots all over some of the lower leaves of my plants. I have been investigating on line and it looks like it might be angular leaf spot, but I can't find what to do about it. I have some neem oil I bought in preparation for problems but have since read this is illegal?? Should I cut the leaves off? The plant looks splendid otherwise (in my very inexperienced opinion ha ha) with many tiny cucumbers on it.
Also, I don't see any flowers .... Just tiny cucumbers.... Don't I need some male flowers to fertilise the cucumbers?? Any advice would be very welcome thank you so much.
Edit: It seems to be getting worse . The one photo I took from above and you can see all the edges of even the newer leaves are starting to go yellow.....

 

I too get this on the bottom two leaves but once it is fruiting I start feeding with tomato food and remove the affected leaves.it's ok after this and doesn't affect the cucumbers.

 

Could be red spider mite.
It looks very similar to me, but difficult to tell without a hand lens.

 

Thank you JWK, I'll watch it for next couple of days. I'll look to see what variety it is and reoort back....

 

Hi Purple Streaks, thank you. Do you recommend any particular feed, and is it right I only use half strength tomato feed on cucumbers.. Something I read last week....? And if so, why is that please?

 

Oh dear Pete, I don't like the sound of spiders... I've been told to mist my aubergibes and peppers to avoid that .... I'm going to get a magnifying glass and have a look.... Thank you!

 

@Bumbalore
My cucumbers get fed Miraclegro just as the tomatoes and everything else in the greenhouse. I also swap some of the Miraclegro feeds for Tomorite, I only use half strength feed on seedlings and young plants.
Red spider mite likes dry conditions so add the cucumbers to the misting regime and generally try and increase the humidity around the cucumbers. I have more problems with red spider mite on cucumbers than peppers.
Red spider mite can be controlled with organic pesticides that use natural soaps and oils, these are contact insecticides so you need to get to all of the plant and spray both sides of leaves, read the label carefully, to make sure it won't affect the plant.
You can also use biological controls and you can buy lacewing larvae and the predatory mite Phytoseiulus from various online suppliers. These are effective, used in many commercial nurseries, but will not remove every single one of the mites.

 

Thank you @NigelJ I will certainly invest in some! My cucumbers are in a polytunnel type greenhouse and it is very humid in there so hopefully it won't be the spider then. I will certainly still take a look and report back!

 

@pete I have had a good look but can't see anything. I couldn't find a magnifying glass but zoomed in on my camera and I couldn't see anything. I did see one tiny red spider on the pot of my pepper seedling (on the other side of the greenhouse up on a high shelf) but haven't seen anything since ....

 

@JWK The variety just says F1 female so I guess you are right then, only female flowers, how interesting, thank you. The leaves are getting slowly worse.... I have some sodium bicarbonate, is that the same as Epsom salts? Do you think I should give it a try? I just want to cut them off but would that be detrimental to the plant?