In the Anguttara Nikaya (Sutta 4.180), the Buddha taught that when any monk taught that such and such were the teachings of the Buddha, we should, without scorning or welcoming his words, compare the words of the monk with the Suttas and the Vinaya (the texts containing the code of monastic discipline). If they are not in accordance with the Sutta-Vinaya, we should reject them. It is only in this way that we will be able to distinguish between a teacher who teaches the true Dhamma and another who has wrong views.
In the Girimananda Sutta, you will learn about some other types of meditations. For example we get to contemplate on the foulness in this body, in the four elements thatare there in any form, including our body. In Girimananda Sutta (AN 10.60) The Buddha tells Ananda:
“Herein, Ananda, a monk contemplates this body upward from the soles of the feet, downward from the top of the hair, enclosed in skin, as being full of many impurities. In this body there are hairs on the head, body hairs, nails, teeth, skin, flesh, sinews, bones, marrow, kidneys, heart, liver, pleura, spleen, lungs, intestines, intestinal tract, stomach, feces, bile, phlegm, pus, blood, sweat, fat, tears, grease, saliva, nasal mucous, synovium (oil lubricating the joints), and urine. Thus he dwells contemplating foulness in this body. This, Ananda, is called contemplation of foulness.”
Once you have calmed your sense faculties, you can follow the instructions of this Girimananda Sutta to do breath meditation:
"[i] Breathing in long, he discerns, 'I am breathing in long'; or breathing out long, he discerns, 'I am breathing out long.' [ii] Or breathing in short, he discerns, 'I am breathing in short'; or breathing out short, he discerns, 'I am breathing out short.' [iii] He trains himself, 'I will breathe in sensitive to the entire body.' He trains himself, 'I will breathe out sensitive to the entire body.' [iv] He trains himself, 'I will breathe in calming bodily fabrication.' He trains himself, 'I will breathe out calming bodily fabrication.'
"[v] He trains himself to breathe in sensitive to rapture, and to breathe out sensitive to rapture. [vi] He trains himself to breathe in sensitive to pleasure, and to breathe out sensitive to pleasure. [vii] He trains himself to breathe in sensitive to mental processes, and to breathe out sensitive to mental processes. [viii] He trains himself to breathe in calming mental processes, and to breathe out calming mental processes.
"[ix] He trains himself to breathe in sensitive to the mind, and to breathe out sensitive to the mind. [x] He trains himself to breathe in satisfying the mind, and to breathe out satisfying the mind. [xi] He trains himself to breathe in steadying the mind, and to breathe out steadying the mind. [xii] He trains himself to breathe in releasing the mind, and to breathe out releasing the mind.
"[xiii] He trains himself to breathe in focusing on inconstancy, and to breathe out focusing on inconstancy. [xiv] He trains himself to breathe in focusing on dispassion,[1] and to breathe out focusing on dispassion. [xv] He trains himself to breathe in focusing on cessation, and to breathe out focusing on cessation. [xvi] He trains himself to breathe in focusing on relinquishment, and to breathe out focusing on relinquishment.
"This, Ananda, is called mindfulness of in-&-out breathing.”