I think this was triggered by my bringing it out to a less sunny location and it freaked out. What can I do for it?

Here is my C. clavata after several months of problems. i just have no idea what is going on.

I have about 12 cacti in varying stages of nitrogen deficiency, and I would like to get them some weak fertilizer water soon. Our spring is about normal, the NWS is predicting a warmer than normal spring here (Seattle). Could I water these plants now, nighttime temperatures are averaging around 45F ...

I am no master of cacti, but I will hazard a guess that they are both the same or similar and that they are Echinopsis hybrids.

Here they are, some say the first is a Graptopetalum.I believe the second to be an Echeveria.
They are both in 4" pots, the grid in the background is 1".

I think we are talking about Mammillaria elegans, most plants are seen solitary, but some have pups.

Whats a freeze cloth?

Thank you all. This has been a wonderful adventure.

I thought I knew it, but I have no memory for a name. Thanks ADHD,

I saw the pics on cactiguide and my thoughts were corrected it is indeed Gymnocalycium baldianum.

I only question that, as I believe I see plants that are very smooth that are baldianum. And was amazed that that lumpy plant could be baldianum

Im not sure about that. Did I say something wrong?

Lifle and Cactus Art see it as a sub set of M rhodantha.