all women are made the same virgins arae virgins. And since you took that first step to have sex you need to schedule a obgyn appointments from here on out
Sex can cause uterine contractions. I get them fairly regularly the morning after my husband and I have sex, and even some spotting.
You may be peeing more because your uterus/pelvic region is swollen and sore. Just like getting a bruise on your arm, or twisting your knee, your pelvic area can get soft tissue damage from having sex and the corresponding swelling will put pressure on your bladder.
These two things together could result in the symptoms you are seeing.
Also, you should always be concerned about STD's. Some STD's can be transferred from birth and so someone who is still a virgin could have an STD even with no sexual activity whatsoever. The only way to know for certain is to have testing done. Now you used a condom, and that's highly recommended for helping prevent STD's so you're almost certainly fine. But if you ever decide to go without, just keep the other bit in mind.
If you ever need to see a doctor and you're worried about your privacy with your regular obgyn, then you can try planned parenthood. (Also, if you don't visit the obgyn yearly, you should start now.)
Spotting is normal for the first 2-3 days following your first time having sex no matter how tight you are. If you have more than that and/or for too much longer, you should probably see a doctor.
The frequent need for urination isn't really consistent with losing your virginity but when you mention it in conjunction with any sort of pain and the fact the bleeding is just spotting when you're not using the bathroom, my mind goes immediately to a UTI (urinary tract infection). It could be bacteria got shoved up your urethra during the movement of sex or you could have contracted it on your own by improper wiping or other things. Either way, you should go in and see a doctor as a UTI will only get worse and more painful, if you do indeed have one, and you need antibiotics. Going to the doctor to see if you have a UTI will NOT let your mom know you had sex as girls get them all the time without having sex. The female urethra is just much shorter than a male's.
Good luck!