Vaginal itch and very irregular period for a month!

Please, PLEASE help me! I have been having vaginal itch since the end of May, around the 21st?? My family went on a vacation the day it happened, we were in the car for 5 hours and by the time we got to the hotel the itch started and got worse that night and just itched SO bad our whole stay. When we went i was supposed to have my period but instead it was a brown discharge, which i have expierinced before and after my period for a few days, so i thought it was normal. I started my period probably 3 days later, it was very light if i remember correctly. Not as heavy as usual, usually u kinda pee blood in the middle of your period right? cause thats what happens w/ me. Anyway, that didn't happen this time and i also usually change my pad 3 to 4 times during the day but i'd only have to eaither wear the one pad all day or just change it once? After a week of that i had the brown discharge for a week or so and i wore a liner, probably a week later i started bleeding again for a week, very light again. I thought this was normal, it has happened to me before. I've had my period for 2 years now so irregularity in when my period comes is normal for me. What caused me to worry is the itching, it would itch during and before and after the periods and discharge. Then the "period" stopped and i continued w/ the brown discharge. A few days ago i started bleeding yet again and thought i'd finally have my period, wrong! It stopped bleeding 3 days later and now the brown discharge AGAIN! During this LONG month of on and off periods it has been itching majorly, a week or so ago i started using baby powder to stop the itch, and it has been working but if i don't put powder on the pad the itch starts again!
~Before this itching and irregularity happened i had to wear a lliner everyday cause i would have a white/ yellowish tinted discharge which i have researched and heard that is totally normal.
~ Also, for the past week or two i have these feelings like i have to go poop but i won't, sometimes i will tho? The other day i had diherria.
PLEASE help me! I don't know whats wrong and i'm worried beyond belief. Could this be serious? Anyone w/ the same problem? It doesn't burn when i pee, it doesn't even itch when i pee? Could it be i sweat to much down there, i'm naturally sweaty, all the time, even my hands since i was little. Could it be my diet, am i not eating healthy enough?
~Also, my blood at times is mucusy on the pad????? and when i wipe?
HELP HELP HELP ME PLEASE! :$ This has been bothering me so much, i'm feeling insecure and not myself. I haven't gone to the OBGYN or drs. yet cause i wanna know if this is common! Please help... ANYONE! I cry sometimes cause i just want this all to stop! Thank ut o every answer!