Amiee,
first of all i want to welcome you.i am very new to the forum too and already i have gotten really good feedback on my problems and the advice has really helped me so far.
It sounds to me like you have all the symptoms of love.when you thought about going out with another boy,you freaked.you couldn't stand the fact that there could be a chance of you falling in love with someone else.you started feeling weird and it was not because you have problems, depression or anxiety.it is because you were punishing yourself for even thinking the thought of liking someone else.you said it yourself, your boyfriend did nothing wrong to you at all.you love him.then you thought about another boy when your friend brought it up so you punished yourself by bringing on all these wierd thoughts,feelings and imaginary symptoms.
I have been put in many situations where i show all the regular symptoms of anxiety and depression.it wasn't because i had these things.it was because i wanted to acknowledge the fact that i had done something wrong to someone or thought a bad thought.i wanted people to be able to see it on my face.the way you described your situation,it sounds like you could be in the exact same predicament.i could be wrong but i know a little something about situations like this.you should really think about this.it could help you to better ananlyze your thoughts so that you will not be tempted to have these thoughts and feelings that make you seem so irregular and not yourself.
As for your boyfriend,it is extremely obvious that you love him.the best advice i can give you for that is to never give up on him no matter what happens in the near future.
Please write me back and tell me what you think.please keep me updated.
Best Wishes.