Bleeding during sex?

If I haven't had sex in a while I bleed... I've been with my boyfriend for a year, but had partners before and it was always the same. I just assumed it was normal until it came up in conversation one day and my SO said he had never experienced it with any past partners. Now I feel embarrassed about it every time it happens and I feel like the only person in the world it happens to! It is often accompanied by a sore-type pain, does anyone else have anything similar? 😞