Need help with tampons!! they hurt and im scared?

so basically i used pads for about 6 years or so and i am now 18 and i wanna start using tampons. i am still a virgin and ive tried using the light absorbency ones before but when i tried to use it, i was too timid to put it in. i wiggled in the opening, and then slowly pushed it in, like really slowly. are you suppose to just wiggle it in through the opening a little and then push hard in one motion so that the whole tampon will be inside of you? the thought of something inside me freaks me out, but i know i have to do this if i ever want to have sex and have kids. any advice on relaxing? and whats the proper insertion technique? (i know that it has to be at an angle, but how fast do i go?) also, how long does it take until the painfulness and fear goes away? thank you so much!