Based on the information it seem like you are on birth control pill and forgot to take it once and had sex and some sperm got inside and wanting to know will be pregnant.
1) The answer is "NO" will not get pregnant by skipping one dose, but make sure that do not happen again.
2) More over do not take the missed pill next day. You are not suppose to take 2 doses in same day as its a hormone and may cause some issues.
3) If forgetting to take medication their are other alternatives available, like intrauterine device
(IUD) where you do not have to worry about taking pill and its safe to go for 5 years , and can be reversed if you want to be pregnant, simple removal of the device will do the trick.
Hope it helps.