I can not see the images very clearly.
But when ever , a patient of mouth ulcers comes to us , we initially treat like this , as apthous ulcers are mostly due to dietary inadequacy.
If in case you have any dental problems causing traumatic apthous ulcers, you need to visit a dentist
If ulcers are associated with other problems like genital ulcers , photo sensitivity , rashes , joint pains
, we think for other causes like Autoimmune diseases , SLE , Behcet's disease.
That's why i said , that follow these medications first , if you won't get relieved , i would advise you testing.