Please help. I'm sorry for posting this again!! Dont kill me.

Could I be pregnant? I sound absolutely crazy and have posted this before. I have stopped worrying about this for a week and have tried to ignore symptoms. 
Last time I had sex with febuary 3rd which was the last day of my period. 
I had sex various times the week before that. 
I am on the pill and my partner wears protection, we don't think we had any accidents but we had sex 4 times in one night and changed the condom each time but one of them didn't feel right so we changed it. 
So from my calculations I have not had sex for 21 weeks. 
I have had 5 lighter periods than usual, still have heavy bright red bleeding for one day and then lighter bleeding for 4 days but not light enough to wear a liner, I still needed a pad (sorry tmi) 
I am still having low pelvic pain and pressure EVERYDAY for most of the day. 
My boobs are also a little bit tingly on and off. 
I also feel movement up around my belly button area that feel a bit like twitches. (This could just be because I have a strange stomach and have to take nexium for stomach issues) 
I have had increased discharge since I last had sex. 
Yes I have taken many pregnancy tests that have been negative and I have gone to my doctor various times. She has said in not pregnant and send me to a urologist because my white cell count in my urine is high but I have no infection! 
I had an ultrasound done month ago which was 6 weeks and 4 days after the last time I had sex to look at my pelvic area to see what was causing pain. The doctor didn't say anything about pregnancy but I have been told but girls on here on another post that they should have been able to see something on an ABDOMINAL PELVIC ULTRASOUND AROUND 6 WEEKS. I still freak out that it could have just been missed. 
I am such a stress head, before anyone says that I need to go and get some help I have, thankyou! I feel a lot better in myself and thinking a lot my positively but still don't understand why I have these symptoms and the doctors don't know why either. 
I have had abdominal pelvic  ultrasound (6weeks) a Pelvic MRI (14weeks) a gastroscopy and a cystoscopy to try to find what is wrong with me. 
I havnt had a pregnancy blood test because the doctor said it wasn't needed since I have had periods and negative at home tests. But I have had a normal blood test to check levels and everything seems fine. 
I'm just so worried that pregnancy could have just been missed! Like I know that's pretty hard but I just don't get why I feel like this. 
I have taken a picture today to show you girls, I know everybody is different but if I was to be 21 weeks pregnant would my stomach be bigger?? 
I have seriously just had enough of feeling this was. If it's not pregnancy, what is giving me the symptoms. Obviously something isn't right if I keep getting a white cell count in my urine of 100, when it is meant to be bellow 10. I looked up what can cause high white cell count if there is no infection and pregnancy was the main cause. So that just totally freaked me out when I seen that. 
If there is negative comments please just ignore this post, I know there a people that have simply had enough of my post but plenty of other girls do it on here as well, not just me. 
I turn here for support. 
My head really doesn't need negative thoughts right now. 
I don't want to be pregnant, and I'm not looking for someone to say yes or no to be pregnant. I just need some type of support in how I can deal with what is going on to get my head around this. I have had a shit 5 months! 
I have been to so many doctors and various appointments and they are trying to work out what's wrong, my tests prove there is something wrong but they just can't work it out. 
Help. So sorry for posting this again. 
Top photo was 8th of June so 3 and a bit weeks ago.
 Second photo was taken today (possibly 21 weeks) 
Last photo is my last pregnancy test done at 17 weeks.