Lump in breast!?

Question

So about 3 days ago I noticed my left breast has a lump inside! It’s the outer side and had felt sore as well. My period is due today or tomorrow, so I thought I just had the normal sore breasts; turns out it was just the one breast... now, my breasts were never the same size. For as long as I can remember the past years, my left breast was always bigger than my right, but Ive never noticed a lump inside! I’m quite-frankly freaking out; thinking it is breast cancer. I have read online that it could be a number of things that are NOT cancer, but I’m not too sure what exactly I’m feeling for. Has anyone else ever had a lump that subsided on its own? Or a lump that was not cancer? I am 23 years old and my breast tissue has always felt a little “lumpy/bumpy”, which I read is actually normal to feel a “ropey consistency”. 
I can feel the lump in my breast without even pushing hard. I can rub my two fingers across/around the breast and just feel it! It does feel like it can move a little and feels like it’s connected to the base of my breast/nipple inside? My right breast has a tiny bump in the same spot, but I have to grab/push to feel it. The left breast is still a little tender to lay on/accidentally hit, but not AS sore. I was thinking maybe it’s just my period making my breast weird? I was going to wait a few days to see if it subsided, but I need to ask someone! Pleaseeee comment if you have had a lump before & what it was. Also if it subsided or needed medication/treatment. 
Thanks for helpin a girl out 💕 sorry for the rant! Lol

Answer

Do you do monthly self-examinations? You should do them monthly about a week AFTER your period starts as your breasts are less tender and lumpy at that point in your cycle. Most breast cancers are found in the tail of the breast (think kind of up by your armpit). More often than not, lumps in someone your age are due to hormonal cycle changes or fibrocystic changes. Caffeine can even cause breasts to feel lumpy. 
I’d check again about a week after your period begins and see what’s going on with it. If you have nipple discharge/leaking, breast dumpling, redness, swelling, change in size/shape go ahead and get ahold of a provider to be seen. If it was me, I’d do self-examination about a week after your upcoming period and then again next cycle to see if there is change.