Bottom side of my mouth just starded to hurt like in the middle i would say pain when i open my mouth and when i touch it and a little bit of swelling?

May have an ulcer: You may have a mild touch of stomatitis (cold sores, canker sore, mucosal irritation due to viral or even bacterial infection). There are over the counter preparations that are good for these types of issues but before going there you'll want to either visualize it yourself or have someone verify it is an ulceration of some sort.