What is chemical pregnancy? and can i get pregnant the next month after my chemical pregnancy?

Right away: The pregnancy hormone/chemical, hcg, rises as a pregnancy grows, and falls if the pregnancy fails. So if you had a miscarriage, the level will fall. A "chemical pregnancy" is a miscarriage that happens so early, that there is never any visible gestational sac by ultrasound. It can feel just like a period, maybe heavier. There's no reason you can't try again the next month.