Any help is needed going insane!

Maddy
Hi guys, I've posted on here before and everyone has been so helpful! 
I was due to come on on the 14th of June, however on the 8th I had a light bleed for 3 days, never heavy and no pains what's so ever! After that, I have had no bleeding since 
I have shortness of breath, put on weight, I have heartburn constantly and my boobs are sore to touch (sorry if TMI)
I've done tests since the 14th all negative with a digital telling me a Bfn today. I have no idea what this could be! If anyone has been through this before or knows any information they could give, it would be a massive help!