dear Bunny, thanks for joining the site.
This transition from a public school into a private school can sometimes not be too favourable, as the adjustment can be a difficult one as the ground rules are much stricter and not so lenient as they are in a public school.
Now that you have already done an online check which does indicate that you are suffering from depression, so your parents know that something is going on and it won't be long before they do realise that you have depression, so it's best for you to tell them, well before they keep asking you questions which will in the long run start to annoy you.
They seem to be very observant which means that they don't want you to suffer without any help, so don't put yourself through agony when they want to help you.
When you find as though these problems are social, then what we do is to attach ourselves to the leading group, knowing that with them you will be safe, but this can lead into being the opposite, because you will be used to do the dirty work for them, and with this it means that you are being lead done the wrong track, and that's why your girlfriend can see this.
So to answer your question 'am I sad or depressed', well sadness can lead people into depression, and that's what is happening to you.
Your girlfriend is a wonder for you, and she can see this a mile away, and so can your parents, that's why it's important for you to talk to them, because a parent notices all the changes in their kids, so please don't block them out, they will start to help you and go to the doctor with you. Geoff. x
