Your post is very confusing and it does not reflect well on your own sense of confidence. You say you regret saying “NO” to better prospects and saying “yes” to this shidduch. Why did this prospect seem better at the time, and why did you turn those down at the time? Is it really this young man that you don’t like or are you suddenly in a panic about losing your daughter?
Is this your first child getting married? Is this your first experience with shidduchim? It sounds like it or at least your first experience with a daughter. Sosme of the posters assume you are the mother and some assume your are the father. I am not going to make an assumption other than you are getting cold feet and you really need to take a step back and take a deep breath. Is your daughter happy? That should be your main concern. This really isn’t about making you happy it is all about your daughter and her right to be happy and fullfilled. If she is happy you should be too. You should not feel a need or a right to control her or even the wedding plans, you had your chance when it was you who was getting married. Now it is your daughter’s turn to plan her own wedding along with her chosson. I am quite sure she has dreamt about this day for a long time. You probably have as well, but they are the King and Queen and what they want are the priority right now as long as it is within reason and within the budget both sets of parents set.
So unless there is something wrong with this chosson that will pose a physical or emotional threat to your daughter, you should really take a step back and take a good hard look at what is going on with you and why you feel this way. You might even need a Rav or a therapist to talk to in order to work out your feelings and have someone to vent to so you don’t cause any damage to your relationship with your daughter and future son-in-law. This is a very emotional time for all of you and there are going to be lots of different feelings and emotions that are going to come to the surface. There will be happy feelings as well as sadness. There will be nervousness, and doubts as well as eagerness and excitement. Weddings bring about all kinds of emotions as well as anxiety and some craziness. So find someone that will help you through this sea of emotions so that you can participate and enjoy your daughter’s happiness.