I collapsed on the bus on tuesday because of panic/anxiety. Its very scary and its a viscious circle because the more you try not to panic the worse it gets, and unless you have people around you that you feel comfortable with it can be very hard. I was with my grandmother and i felt bad because usually she's the one that relies on me, and we were on the way to the hospital for her to have a check up. Someone let me sit down which helped a lot, but i'm worried about it happening at uni (it didn't happen last year) because people fussing around me would make it worse. I'm also worried because my mum and my boyf who are the only people to have seem me have panic attacks won't be around to calm me down.
You should try and see someone, they can help you talk through things and suggest coping mechanisms.