Op. Some years ago, I knowingly took some legal highs at a party. I was very naive about drugs of any kind, being a highly anxious person, I have always been scared about them. However I was told they were herbal and 'natural' and it was before there was so much publicity on how dangerous they are. I was the only one not taking them and basically peer pressure and low self esteem had me taking them. It was a weekend and the DC were on contact with their father.
To cut a long story short, I took a terrible reaction, lost my vision, passed in and out of consciousness, hallucinated and felt very strongly that I was going to die. I didn't and it eventually wore off. That, was only the start.
The trauma of the experience, the guilt that I took such a stupid risk, the effect on my body and brain... 24 hours later I began to have what ended up being a nervous breakdown. I was under a crisis team, nearly sectioned and believed I had damaged my brain forever. It took a year to recover and I was left with PTSD.
A report was passed on to social services and yet they never investigated or tried to take the kids away. The professionals involved knew how much I loved my children and the guilt of what I had done to myself was what kept me ill for so long.
Anyways. You are not going to bbc investigated. You are not going to lose your kids. Your heart is fine, the coke is not in your system. Your anxiety is causing the raised heart beat. Nothing is going to happen to you, it's been days now. You have got to drink plenty of water, try to rest and be kind to yourself. You have had a terrible fright but it will pass.