Im feeling super sick

So a few days ago a friend of mine started to get really close with another friend of theirs (who im not all that close with). I’m really happy for them, but later it started to hit me that everything was gonna feel different. Its been three days and I’m constantly having panic attacks. Every time I even try to look at them or text them I feel physically sick. Nothings been really enjoyable for me, and I don’t want to feel like this anymore.