Help! What’s wrong with my cucumber plant. Tendrils & veg drying/yellowing, holes in leaves

[Emma_enthusiasticgardener]

I really love my cucumber plants but all three appear to not be doing so well after originally producing large healthy cucumbers. The ends of the fruits are all now drying out and yellowing, as are the tendrils. They're producing far less fruit as well all of which now don't seem to be growing of filling out or retaining their colour. I have been doing a little pruning - pinching out the new growths of most of the nodes and cutting off some excess larger leaves, all new growth at the top seems to be healthy. I noticed some leaf miner on some of the leaves so have squashed these. The leaves also seem to have tiny little white holes in and the plant occasionally wilts but seems to be fine after a water for the next day or so. I water it about a glass of water every day or every other day upon seeing it start to wilt a little. I used to feed them once weekly with a diluted homemade cumphrey and nettle feed but have stopped this for the last week in case the problems were from over feeding or an excess amount of nutrients. They are all kept inside in pots - I mulch them with compost every few weeks. I am at a bit of a loss as to what the problem is. Please do help!