Though it requires manual examination as there are many etiological factors behind lumps in gums. It can be due to allergic reaction, eating too much of acidic juice or spicy foods, can be sometimes due to toothpastes also.
But the main reason is tooth infections that have gone down into the roots. So, you should visit your nearby local dentist.
For time being you can try over the counter gum paints. Apply it over the gums and gently massage with your fore finger.
For more info on gum diseases and their treatment you can visit the link...http://www.identalhub.com/dental-natural-remedies-for-gum-diseases-560.aspx
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