Please don't feel a fool, or indeed a coward. You are neither. Your post made me well up, I'm so sorry you are facing into this now. Every lady here will relate to your feelings of apprehension & anguish, regardless of their stage in life.
The colposcopy is a wretched examination but, in my experience (I've had more than I care to remember & I'm only 31), it is never as bad as I think it is going to be. Do you have somebody who can accompany you to the appointment? It is well worth asking a friend to go with you. I can honestly tell you I've never experienced any pain during colposcopy. I've had countless biopsies & smears & endocervical brushes &, while they're not pleasant, they have not been painful. Even my last one which was done while I was breastfeeding was fine (breastfeeding has the same effect on the vagina/cervix as menopause). As for the indignity? I can assure you, though it feels unspeakable to you to be in the required position, the person performing your colposcopy will likely have done so many that there is nothing they won't have seen before &, besides, we are all the same! Please try not to worry about that aspect of it, the more relaxed you can be the smoother it will go. There are usually a couple of nurses or health care assistants in the room too to assist the colposcopiSt & to help put you at your ease as far as possible.
Regarding your fears about the outcome. There isn't much anyone can say at this stage to alleviate those. Just like there is no point in me saying try not to worry because I know you will. With any luck it will be something simple that can be dealt with easily. I'm a doctor (NOT gynae) and at medical school we always got taught the saying "common things are common", so hopefully it will be something common causing your symptoms & not something sinister.
Once again, please don't feel a fool or a coward (you should change your username!) because you most certainly are not either of those things and you must keep telling yourself that.
I do hope you have somebody who can go along with you to the colposcopy. It really helps. Then you can go for a coffee or a walk afterwards to clear your mind & relax knowing it's all over & done with.
I really really hope it goes well for you. I will be thinking of you. If you can, pop back on here & let us know how it went. You can always message me if you have any other questions about the colposcopy as, like I said, I've had so many it's silly!
Warm thoughts to you,