A woman who has been guided to Islam fears for herself and is suffering from waswaas (insinuating whispers of the Shaytaan)

Allah has given man in this world that which will help him to worship and obey Him as He has commanded. He has given him strength in himself and has created him in the best mould (cf. al-Teen 95:4). Then He sent His Messengers to mankind to tell them the way to worship and obey Him, and He sent down His Books to mankind, and gave the ability to understand and learn. 

The slave has to seek the means which will help him to follow the path of obedience and faith. These include: 

1 – Striving to perform the obligatory duties as prescribed in sharee’ah, and doing so regularly. 

2 – Striving to keep away from haraam things and sin, because that has a great effect on man’s heart. 

3 – Taking time to read Quran. What we should note here is that the kind of reading Quran which has a beneficial effect on the one who reads it is that which is accompanied by thinking and pondering the meanings of the verses of the Quran. Allah has told us of the effect of the Quran on His believing slaves, as He says (interpretation of the meaning): 

“and when His Verses (this Quran) are recited unto them, they (i.e. the Verses) increase their Faith”[al-Anfaal 8:2] 

“Allah has sent down the Best Statement, a Book (this Quran), its parts resembling each other (in goodness and truth) (and) oft‑repeated. The skins of those who fear their Lord shiver from it (when they recite it or hear it). Then their skin and their heart soften to the remembrance of Allah”[al-Zumar 32:23]

4 – Remembering Allah (dhikr) and persisting in doing so. Beneficial dhikr is that which is done in the heart and on the lips. Allah says (interpretation of the meaning): 

“verily, in the remembrance of Allah do hearts find rest”[al-Ra’d 13:28]

5 – Calling upon Allah (du’aa’) and turning to Him. Among the du’aa’s concerning this is that which is described in the hadeeth of the Prophet (peace and blessings of Allah be upon him): 

“There is no-one who is afflicted by distress and grief, and says: ‘Allahumma inni ‘abduka ibn ‘abdika ibn amatija naasyati bi yadika, maada fiyya hukmuka, ‘adlun fiyya qadaa’uka. As’aluka bi kulli ismin huwa laka sammayta bihi nafsaka aw anzaltahu fi kitaabika aw ‘allamtahu ahadan min khalqika aw ista’tharta bihi fi ‘ilm il-ghayb ‘indaka an taj’al al-Qurana rabee’ qalbi wa noor sadri wa jalaa’ huzni wa dhihaab hammi (O Allah, I am Your slave, son of Your slave, son of Your maidservant; my forelock is in Your hand, Your command over me is forever executed and Your decree over me is just. I ask You by every name belonging to You which You have named Yourself with, or revealed in Your Book, or You taught to any of Your creation, or You have preserved in the knowledge of the Unseen with You, that You make the Quran the life of my heart and the light of my breast, and a departure for my sorrow and a release for my anxiety),’ but Allah will take away his distress and grief, and replace it with joy.” He was asked: “O Messenger of Allah, should we learn this?” He said: “Of course; everyone who hears it should learn it.” 

6 – Striving to reduce your attachment to this world and developing an attachment to the Hereafter, for being preoccupied with the worries of this world makes a person more worried and anxious, and makes the problems that he is going through occupy all his thoughts and give him sleepless nights. 

7 – Doing things to help one relax and dispel worry, such as keeping company with righteous people, relaxing in permissible ways and giving oneself variety to avoid a boring routine. 

If you feel the need to visit a psychologist and consult him, there is nothing wrong with that, so long as you beware of the deviant principles of some doctors.