So I never write on boards like this but since this is important I thought I'd ask for outside advice. 

I'm not sure when I ovulated, my green days on Glow were July 13-19, with the 17th having the highest likelihood of pregnancy. I've had sex the 11th, 20th, & 22nd of this month. My period is expected this Sunday, July 31st. 

For 5 days now I've had a dull ache in my lower back, kinda similar to the pain I have during my period, and some weird heartburn/indigestion feelings. I put it like that because I don't really know how else to describe it. I feel kinda gassy, bubbly, really, like I need to burp. I haven't eaten anything that would cause that. I've also had a kinda tingly feeling in my breasts. These feelings are on and off throughout the day but are definitely stronger at night. I've been perfectly fine otherwise so I don't know what else could be causing these symptoms. The fact that I've had them for several days in a row is what makes me suspect pregnancy. (Although honestly I started to suspect on like the second day.) 

Do these sound like pregnancy symptoms to y'all? If so, when could I start testing? I know there are some HPTs that claim to get a result days before your expected period but I'm not sure how accurate those are. 

Thanks :)