I raised $1m for a pre-seed and I feel super scared and like a imposter - I will not promote

Being vague purposefully I am in a high paying and stable job and 1 month ago had a quite a good idea and got some little traction on it and basically decided that I wanted to go full time on it. The traction I got is good but I don’t really think it is a sure fire. I started pitching to investors and within a few calls managed to get a big name investor wanting to put their money into my company. All together they pledged $1m (completing my entire raise amount). Deep inside I don’t think I ever thought I w