Fear of being sick or fainting in public

Hello, I'm new to all this but desperate for some help.

ive had this on and off for about 4 years but now it is back and occurring more often. Whenever I go out, to a restaurant, shopping centre, cinema, anywhere I will get this feeling in the pit of my stomach before leaving, sweaty palms, dry mouth feeling like I don't want to go. But I just think I always have to challenge my anxieties so I go anyway. But once I'm out I will feel sick and sometimes light headed and then I can't concentrate on having a nice time and I'm always trying to figure out where is the nearest bathroom in case I need to be sick or pass out where not many people can see me because I'm embarrassed. It is getting to the point where i don't won't to go out anymore. I thought at first I as allergic to something, but if i eat the same things at home nothing happens - it's just when I'm out in public.

i should also mention that whilst I am a healthy 21 year old, I have been known to both pass out and be sick in public, so I know it is embarrassing but know it passes quickly. 

Any tips on how I can deal with this? And do you think it's anxiety disorder?

I have had the same thing happen to me now for years I dread going anywhere because in worried I'm going to pass out sometimes I get so worked up I go into a full blown panic attack it's horrible !! I'm 31 weeks pregnant and I have been so sick past few weeks I don't even want to leave my house I really don't know what to do anymore this is very dibilitating I feel dizzy and all off balance and I get so scared when it comes on

I also have a fear of fainting in public. The fear is strongest when its really hot out, so I dont even go out on hot days. It sounds like you have an anxiety disorder, sometimes a disorder only rears its ugly head in certain situations and places. All I can say about the fainting is it really is all in your head, think of all the times youve gone out and have not fainted, that usually comforts me, as a reminder that its only anxiety..Im not really goign to faint.

Yes I think you are dealing with a anxiety disorder, but the great news is that you can over come it. It's all fear based, you are already working your self up before you go- your so worried about what could happen your putting your mental state into a panic before you step out the door so while you are out your in a flight or fight panic mode your telling your brain your not safe out side. It you do not know what that is just google it( flight or fight) Your letting" what if thinking run your life" break it down so you can bear the fear. What I mean play it out so you lose some of the worked up fear. So what if you pass out? You said you have before rite, and your still here, so the Worste case is your a little embarrassed but in the big pitcher of life embarrassing moments aren't to bad rite? There are homeless people who will not eat and don't know how they are going to get back on there get with no hope, so in the big pic of life being embarrassed isn't to bad. And tell your self that so you can minimize the fear of it and that will help you having the panic feelings. When you lose the fear of "what if" happening events you will feel the anxiety start to lift. I hope that helps also talk to your doctor. From personal experience the more you run from it and when your out go to the bathroom to feel safe your telling your self subconsciously that your in real danger and the anxiety will continue to grow, I had to start working on now matter where I am in safe, I used to have to run out of the room into the hall way to"catch some air" then it dawned on me the air is no different from one room to the next and started telling my self what ever happens I'll deal with it at the time if it does ,. but I'm not going to constantly focus on it Because I was telling my self my fears where true. I set a rule for myself I cannot worry unless it is truly happened and that trick has been working for me. I hope that helps you. Best if luck