Call the crisis team, tell them you can't talk, but can write down your feelings/situation, they may be able you to give you a phone number to text, or definitely will have an email address.
If it's too much to write again, copy and paste the messages you already sent to the other social worker.
Another option is to use Relay, I find talking on the phone really hard, so I use relay, I type and they read out to the person I called what I type, you have the option for them to type what the person you called says, but I don't think you need that, just for someone to read your message so you can explain all you have said here.
www.relayuk.bt.com
My heart really goes out to you, I think coming off your ADHD meds 'cold turkey' has caused this crisis, they are the sort of medicine that are dangerous to just stop.
You are an amazing Mum, I know you can't see it right now, but you have brought up a 19yr old who is working & thinks you are a great Mum, a 15 yr old & a 10 yr old, despite all life has thrown at you, you have done an amazing job, & will again with help to get through this crisis.
Your house looks like a lovely home, full of love, it's just a little untidy at the moment, but it's not bad! When you can just tackle one job at a time, but right now, it's not important.
If you feel that you are at the end, call 999, they will help you and find a temporary place for your boys until you are well enough to care for them. They need their Mum, you are an inspiration to them despite how you feel right now, you have loved and provided for them despite all your challenges- that takes an amazingly strong woman, and you will be that woman again, with a little help and getting your meds right.
Please keep talking to us here, and please, please keep safe.
It's god to have an emergency plan for moments of crisis, but for now just pop on a piece of paper the essentials-
Have the emergency numbers written down for you to call if you can no longer cope. And your repeat prescription so you can give it to the medical staff.
If you can, write down any meds the boys are on so their temporary carers know & anything specific to them- just basics .
You have got this, it's a period of time and you will come out the other side because you are amazing!