I've been on my period for 10 days now, could that mean i'm pregnant ?

Unlikely: Having a regular period means one is not pregnant. Having sex after the period means one could become pregnant on the current month. If the next period comes and is a normal regular one, it means one is not pregnant, again. If worried, one can do a urine pregnancy test the week after missing a period or after having a "weird" period, or 3 weeks after having sex.

Probably not: Having a period is usually a good indication that a woman is not pregnant. However, if you have been bleeding for 10 days, it is a good idea to see a doctor. It is not normal to have a period lasting that long and a woman can become anemic from too much blood loss. It could also be sign of a sexually transmitted disease, and if you have had unprotected sex then you need to be checked.