Social services advice needed

Hi, its a long read sorry in advance. I have 2 children 15 Yr and 11 Yr my youngest child my son has complex learning disabilities and a medical disability, He is now going to a specialist school since September, his epilepsy recently got bad because of trouble getting the new medication he was put on by his neurologist his doctor refused twice to prescribe it not sure why. (BTW after he has a seizure he becomes confused, unbalanced on his feet and disoriented) a few weeks ago he came home from school via school transport and was quite pale and wobbly on his feet he fell into a door and a lump developed I sat him down and applied a cold compress I let his dad know who was at work and also told him 2 days later quite a big bruise had came up I kept him off school the next day to monitor him the bruise didn't heal until a week later but school flagged it up with social services prior to this his weight went down quite a bit due to medication we booked an appointment with a nurse who works with school to seek help and advice about his lack of appetite she was not concerned at the time of speaking to me but a week later she also called social services. She and the social worker requested he get a medical and photo's were taken of the bruising (I felt like a criminal) the nurse then requested he go to hospital to help him get on new medication and monitor his weight which did help me as now we have an appointment with a dietitian and after 5 yes finally have an epilepsy nurse. Dad forgot the timing of when I made him aware of the incident at home which caused the bruising (we don't live together) which left discrepancies so social services are concerned whilst at hospital my daughter 15 came to visit us with dad and young cousin whilst there daughter and cousin played in the play den on the ward for a bit then asked to go to the shop whilst the kids dad was with them a nurse came to see me with a piece of paper which had on one side "please help me" which my son or daughter didn't write but the nure still showed the social worker. My daughters school spike with my daughter and showed her the note and she told them she didn't write it but it appears to be falling on deaf ears whilst questioning her the teacher told her to score 0 to 10 if she is happy at home he told her not to say 10 or 9 as no child can be that happy he made her feel uncomfortable and so she said 5 because she wants us to move to a bigger house (we live in a small 2 bed terrace house) the social worker has now upped the case from child in need to child protection and I'm terrified even though I know I have not done anything wrong and just need support. Can anyone please give me advice on what I should do now. Thanks in advance.