If your a virgin then everytbing is probably still too big to be comfortable, especially if you aren't relaxed. It takes time to open up. Lube? Have you tried that? Tiny steps, take it slowly, get aroused, make sure you're properly wet before trying to insert anything. Insert a finger slowly, little by little, not all in one great wham. Stop if it hurts and just stay there, relaxing, maybe wiggling your finger a bit. Rub your clit at the same time, imagine anything that turns you on. And use plenty of lube. If your hymen isn't broken, that could be makimg it difficult too, so just go nice and slow, wet and warm.